The role of oxidative stress and NF-kappaB activation in late diabetic complications

Revolutionizing drug delivery strategies with probucol to combat oxidative stress in retinal degeneration: A comprehensive review

Localized oxidative stress plays a key role in the development of retinal degenerative diseases, with diabetic retinopathy (DR) being one of them, contributing significantly to this vision-threatening complication of diabetes. Increased oxidative burden leads to dysfunction across various retinal cell types, including vascular endothelial cells, neurons, glial cells and pericytes. Importantly, even after achieving normalized glycemia, the detrimental effects of oxidative stress persist. Nonetheless, growing data highlights the therapeutic potential of antioxidants in safeguarding vision. However, extensive clinical trials using traditional antioxidants have produced mixed results. Therefore, probucol, known for its ability to limit vascular oxidative stress, decrease superoxide generation, and improve endogenous antioxidant activity, is a promising candidate explored in this review. In addition to describing probucol, this review will explore novel therapeutic formulation strategies by incorporating bile acid into probucol-loaded nanoparticles to enhance drug delivery to the posterior segment of the eye for more effective management of DR. The integration of bio-nanotechnology with probucol and bile acids represents a promising avenue for developing effective therapies for DR, addressing the limitations of traditional antioxidant treatments.

Evaluation of Complete Blood Count Parameters in Patients With Diabetes Mellitus: A Systematic Review

Background and Aims

Several studies were performed to evaluate the relationship between CBC and patients with diabetes mellitus (DM). In this review, we discussed the prognostic value of CBC parameters in DM patients.

Methods

English literature was searched and retrieved from the Google Scholar search engine and PubMed database (1980-2024). "Diabetes mellitus," "Blood cell count," "Mean platelet volume," "Leukocytes," and "Inflammation" were used as keywords.

Results

DM increases vascular inflammation and oxidative stress, while vascular inflammation affects erythropoiesis and red blood cell deformation, thus increasing red cell distribution width (RDW). Mean platelet volume (MPV) is another useful prognostic biomarker for DM patients. Additionally, elevated neutrophil-lymphocyte ratio (NLR) levels are associated with poor glycemic control in T2DM patients, so it can be used as a screening tool in diabetic follow-up.

Conclusion

RDW can be used as a valuable independent biomarker to assess the prognosis of patients with DM. MPV can also be used as a noninvasive, widely available, and low-cost marker as a key factor as well as a Prognostic/diagnostic biomarker that could be used for DM patients. Total white blood cell count, NLR, Mean platelet volume lymphocyte ratio (MPVLR), and monocyte to high-density lipoprotein ratio (MHR) are valuable biomarkers in predicting DM.

Biological functions of the m6A reader YTHDF2 and its role in central nervous system disorders

N6-methyladenosine (m6A) is a prevalent mRNA modification in eukaryotic cells, characterized by its reversible nature. YTH structural domain family protein 2 (YTHDF2), a key reader of m6A, plays a crucial role in identifying and binding m6A-containing RNAs, thereby influencing RNA metabolism through various functional mechanisms. The upstream and downstream targets of YTHDF2 are critical in the pathogenesis of various central nervous system (CNS) diseases, affecting disease development by regulating signaling pathways and gene expression. This paper provides an overview of current research on the role of YTHDF2 in CNS diseases and investigates the regulatory mechanisms by which YTHDF2 influences the development of these conditions. This exploration aims to improve understanding of disease pathogenesis and offer novel insights for the targeted prevention and treatment of neurological disorders.

Relationship between oral hypofunction and salivary biomarkers in older adults: a cross-sectional study

BACKGROUND

Oral health problems have increased among older adults. Oral hypofunction is characterized by seven signs and symptoms: oral uncleanness, oral dryness, decline in occlusal force, decline in the movement function of the tongue and lips, decline in tongue pressure, decline in masticatory function, and decline in swallowing function, the latter being a significant risk factors for oral frailty. Recent research has suggested that salivary biomarkers can be used to assess not only oral diseases, including dental caries and periodontitis, but also systemic diseases, such as cancer and diabetes mellitus. This cross-sectional study investigated the relationship between oral hypofunction and the levels of salivary biomarkers.

METHODS

In total, 116 patients, aged 65 years or older, were included in this cross-sectional study. If three or more signs or symptoms in seven kinds of tests met the criteria of each test, oral hypofunction was diagnosed. The levels of biomarkers in the saliva collected from the patients were analyzed using an enzyme-linked immunosorbent assay.

RESULTS

In total, 63.8% of patients were diagnosed with oral hypofunction. Multivariable linear regression analysis showed that calprotectin levels in the saliva were significantly related to oral moisture and masticatory function. Furthermore, 8-OHdG levels in saliva were associated with the movement function of the tongue and lips and oral hygiene level, and salivary AGE correlated only with the movement function of the tongue and lips. Multiple logistic regression analysis revealed that calprotectin levels in the saliva were significantly correlated with the prevalence of oral hypofunction, even after adjusting for age, sex, and periodontal status. However, none of the biomarker levels in the saliva had a significant relationship with the number of examinations outside the reference range.

CONCLUSIONS

Calprotectin, 8-OHdG, and AGE levels are associated with oral hypofunction in older adults.

Delivery technologies for therapeutic targeting of fibronectin in autoimmunity and fibrosis applications

Fibronectin (FN) is a critical component of the extracellular matrix (ECM) contributing to various physiological processes, including tissue repair and immune response regulation. FN regulates various cellular functions such as adhesion, proliferation, migration, differentiation, and cytokine release. Alterations in FN expression, deposition, and molecular structure can profoundly impact its interaction with other ECM proteins, growth factors, cells, and associated signaling pathways, thus influencing the progress of diseases such as fibrosis and autoimmune disorders. Therefore, developing therapeutics that directly target FN or its interaction with cells and other ECM components can be an intriguing approach to address autoimmune and fibrosis pathogenesis.

Indole-pyridine carbonitriles: multicomponent reaction synthesis and bio-evaluation as potential hits against diabetes mellitus

Background: Diabetes mellitus is a significant health disorder; therefore, researchers should focus on discovering new drug candidates. Methods: A series of indole-pyridine carbonitrile derivatives, 1-34, were synthesized through a one-pot multicomponent reaction and evaluated for antidiabetic and antioxidant potential. Results: In this library, 12 derivatives - 1, 2, 4, 5, 7, 8, 10-12, 14, 15 and 31 - exhibited potent inhibitory activities against α-glucosidase and α-amylase enzymes, in comparison to acarbose (IC50 = 14.50 ± 0.11 μM). Furthermore, kinetics, absorption, distribution, metabolism, excretion and toxicity and molecular docking studies were used to interpret the type of inhibition, binding energies and interactions of ligands with target enzymes. Conclusion: These results indicate that the compounds may be promising hits for controlling diabetes mellitus and its related complications.

Oxidative stress in intervertebral disc degeneration: Molecular mechanisms, pathogenesis and treatment

Low back pain (LBP) is a leading cause of labour loss and disability worldwide, and it also imposes a severe economic burden on patients and society. Among symptomatic LBP, approximately 40% is caused by intervertebral disc degeneration (IDD). IDD is the pathological basis of many spinal degenerative diseases such as disc herniation and spinal stenosis. Currently, the therapeutic approaches for IDD mainly include conservative treatment and surgical treatment, neither of which can solve the problem from the root by terminating the degenerative process of the intervertebral disc (IVD). Therefore, further exploring the pathogenic mechanisms of IDD and adopting targeted therapeutic strategies is one of the current research hotspots. Among the complex pathophysiological processes and pathogenic mechanisms of IDD, oxidative stress is considered as the main pathogenic factor. The delicate balance between reactive oxygen species (ROS) and antioxidants is essential for maintaining the normal function and survival of IVD cells. Excessive ROS levels can cause damage to macromolecules such as nucleic acids, lipids, and proteins of cells, affect normal cellular activities and functions, and ultimately lead to cell senescence or death. This review discusses the potential role of oxidative stress in IDD to further understand the pathophysiological processes and pathogenic mechanisms of IDD and provides potential therapeutic strategies for the treatment of IDD.

Biomarkers of Oxidative Stress in Systemic Lupus Erythematosus Patients with Active Nephritis

Oxidative stress plays an important role in systemic lupus erythematosus (SLE) and especially in lupus nephritis (LN). The aim of this study was to compare redox-related biomarkers between patients with active LN, quiescent SLE (Q-SLE) and healthy controls (HC) and to explore their association with clinical characteristics such as disease activity in patients. We investigated levels of plasma free thiols (R-SH, sulfhydryl groups), levels of soluble receptor for advanced glycation end products (sRAGE) and levels of malondialdehyde (MDA) in SLE patients with active LN (n = 23), patients with quiescent SLE (n = 47) and HC (n = 23). Data of LN patients who previously participated in Dutch lupus nephritis studies and longitudinal samples up to 36 months were analyzed. Thiol levels were lower in active LN at baseline and Q-SLE patients compared to HC. In generalized estimating equation (GEE) modelling, free thiol levels were negatively correlated with the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) over time (p < 0.001). sRAGE and MDA were positively correlated with the SLEDAI over time (p = 0.035 and p = 0.016, respectively). These results indicate that oxidative stress levels in LN patients are increased compared to HC and associated with SLE disease activity. Therefore, interventional therapy to restore redox homeostasis may be useful as an adjunctive therapy in the treatment of oxidative damage in SLE.

Advanced Glycation End Products in Health and Disease

Advanced glycation end products (AGEs), formed through the nonenzymatic reaction of reducing sugars with the side-chain amino groups of lysine or arginine of proteins, followed by further glycoxidation reactions under oxidative stress conditions, are involved in the onset and exacerbation of a variety of diseases, including diabetes, atherosclerosis, and Alzheimer’s disease (AD) as well as in the secondary stages of traumatic brain injury (TBI). AGEs, in the form of intra- and interprotein crosslinks, deactivate various enzymes, exacerbating disease progression. The interactions of AGEs with the receptors for the AGEs (RAGE) also result in further downstream inflammatory cascade events. The overexpression of RAGE and the AGE-RAGE interactions are especially involved in cases of Alzheimer’s disease and other neurodegenerative diseases, including TBI and amyotrophic lateral sclerosis (ALS). Maillard reactions are also observed in the gut bacterial species. The protein aggregates found in the bacterial species resemble those of AD and Parkinson’s disease (PD), and AGE inhibitors increase the life span of the bacteria. Dietary AGEs alter the gut microbiota composition and elevate plasma glycosylation, thereby leading to systemic proinflammatory effects and endothelial dysfunction. There is emerging interest in developing AGE inhibitor and AGE breaker compounds to treat AGE-mediated pathologies, including diabetes and neurodegenerative diseases. Gut-microbiota-derived enzymes may also function as AGE-breaker biocatalysts. Thus, AGEs have a prominent role in the pathogenesis of various diseases, and the AGE inhibitor and AGE breaker approach may lead to novel therapeutic candidates.

Polyol pathway and redox balance in diabetes

Diabetes is a major public health disease that is globally approaching epidemic proportions. One of the major causes of type 2 diabetes is either a defect in insulin secretion or insulin action which is usually caused by a combination of genetic and environmental factors. Not only these factors but others such as deregulation of various pathways, and oxidative stress are also known to trigger the redox imbalance in diabetics. Increasing evidences suggest that there are tight interactions between the development of diabetes and redox imbalance. An alternate pathway of glucose metabolism, the polyol pathway, becomes active in patients with diabetes that disturbs the balance between NADH and NAD+ . The occurrence of such redox imbalance supports other pathways that lead to oxidative damage to DNA, lipids, and proteins and consequently to oxidative stress which further ascend diabetes and its complications. However, the precise mechanism through which oxidative stress regulates diabetes progression remains to be elucidated. The understanding of how antioxidants and oxidants are controlled and impact the generation of oxidative stress and progression of diabetes is essential. The main focus of this review is to provide an overview of redox imbalance caused by oxidative stress through the polyol pathway. Understanding the pathological role of oxidative stress in diabetes will help to design potential therapeutic strategies against diabetes.

Role of Oxidative Stress in Diabetic Cardiomyopathy

Type 2 diabetes is a redox disease. Oxidative stress and chronic inflammation induce a switch of metabolic homeostatic set points, leading to glucose intolerance. Several diabetes-specific mechanisms contribute to prominent oxidative distress in the heart, resulting in the development of diabetic cardiomyopathy. Mitochondrial overproduction of reactive oxygen species in diabetic subjects is not only caused by intracellular hyperglycemia in the microvasculature but is also the result of increased fatty oxidation and lipotoxicity in cardiomyocytes. Mitochondrial overproduction of superoxide anion radicals induces, via inhibition of glyceraldehyde 3-phosphate dehydrogenase, an increased polyol pathway flux, increased formation of advanced glycation end-products (AGE) and activation of the receptor for AGE (RAGE), activation of protein kinase C isoforms, and an increased hexosamine pathway flux. These pathways not only directly contribute to diabetic cardiomyopathy but are themselves a source of additional reactive oxygen species. Reactive oxygen species and oxidative distress lead to cell dysfunction and cellular injury not only via protein oxidation, lipid peroxidation, DNA damage, and oxidative changes in microRNAs but also via activation of stress-sensitive pathways and redox regulation. Investigations in animal models of diabetic cardiomyopathy have consistently demonstrated that increased expression of the primary antioxidant enzymes attenuates myocardial pathology and improves cardiac function.

Lycopene: A Potent Antioxidant for the Amelioration of Type II Diabetes Mellitus

Nutrition is of utmost importance in chronic disease management and has often been described as the cornerstone of a variety of non-communicable diseases. In particular, type II diabetes mellitus (T2DM) represents a prevalent and global public health crisis. Lycopene, a bright red carotenoid hydrocarbon found in tomatoes and other red fruits and vegetables, has been extensively studied for its biological activities and treatment efficiency in diabetes care. Epidemiological investigations indicate that lycopene has potential antioxidant properties, is capable of scavenging reactive species, and alleviates oxidative stress in T2DM patients. This review aims to summarize the characteristics and mechanisms of action of lycopene as a potent antioxidant for T2DM. In addition, the evidence demonstrating the effects of lycopene on glycemic control and oxidative stress biomarkers in T2DM are also highlighted using animal and human studies as literature approach.

Salvia hispanica L. seeds extract alleviate encephalopathy in streptozotocin-induced diabetes in rats: Role of oxidative stress, neurotransmitters, DNA and histological indices

CONTEXT

Diabetes mellitus (DM) is a metabolic disorder and may lead to cognitive dysfunctions.

OBJECTIVE

The aim of this work is to evaluate the potency of Salvia hispanica L. seeds (S. hispanica L.) (chia seeds) petroleum ether extract in attenuating brain complications associated with streptozotocin (STZ) induced diabetes in rats.

MATERIALS AND METHODS

Phytochemical composition of the seeds extract, macro and micro elements, vitamins, protein, carbohydrate and caloric values were estimated. Diabetes was induced by a single intraperitoneal injection of STZ (60 mg/kg body weight (b.wt)). Glibenclamide as a reference drug was also evaluated. The biochemical evaluation was done by measuring levels of glucose, insulin, α amylase, glutathione (GSH), superoxide dismutase (SOD), malondialdehyde (MDA), dopamine (DA), serotonin (5-HD), noradrenaline (NE), acetylcholinesterase (AchE), tumor necrosis factor-α (TNF-α), DNA fragmentation pattern and the histopathological profile of the brain hippocampus region.

RESULTS

Gas chromatography/mass spectrometry (GC/MS) analysis revealed the presence of twenty-five fatty acid esters and twenty-two compounds. Column chromatography led to the isolation of nine compounds. Treatment with the seeds extract revealed improvement of the measured parameters with variable degrees.

CONCLUSION

Chia seeds extract succeeded to attenuate the neurodegeneration in diabetic rats. Thereafter, it could be potentially used as a new dietary supplement against diabetic encephalopathy.

Preliminary results of effect of barley (<em>Hordeum vulgare L.</em>) extract on liver, pancreas, kidneys and cardiac tissues in streptozotocin induced diabetic rats

Diabetes mellitus (DM) and its complications impose a significant burden on patients and the health care system. In the Traditional Persian Medicine (TPM), barley is recommended for treatment of DM. This study sought to assess the effect of barley seed aqueous extract on hepatic, pancreatic, renal and cardiac tissues in normal (non-diabetic) and Streptozotocin-induced diabetic rats. Twenty-one male Wistar rats were randomly divided into diabetic and non-diabetic groups. Diabetes was induced by single intraperitoneal injection of Streptozotocin. After one week, the diabetic and non-diabetic groups were randomly divided into control and barley seed extract subgroups namely N group (non-diabetic control rats), S group (seed extract treated non-diabetic rats), D group (diabetic control rats) and DS group (seed extract treated diabetic rats). After 6 weeks, all rats were sacrificed for histopathological analysis and specimens were stained routinely for histological studies. The abnormal histological signs significantly decreased in the DS group compared to D group. Also, protective effects of barley seed extract against histopathological changes were seen in S group compared to N group.These findings suggest that barley seed extract exerts a protective effect on different tissues in diabetes.

Neutrophil-to-lymphocyte ratio is associated with coronary microvascular dysfunction in type 2 diabetes mellitus patients

AIMS

Our study is aimed to investigate the relationship between neutrophil-to-lymphocyte ratio (NLR) and coronary microvascular dysfunction (CMD) in type 2 diabetes mellitus (T2DM) patients.

METHODS

We retrospect the consecutive medical files of 160 T2DM patients and recorded their clinical information and laboratory findings. Patients were divided into CMD group (n = 87) and non-CMD group (n = 73). We compared the NLR values of the two groups. Meanwhile we also observed the prevalence of CMD at different NLR levels. Then, logistic regression and ROC analysis were performed.

RESULTS

NLR value of CMD group was significantly lower than non-CMD group (2.01 ± 0.74 vs 2.53 ± 0.69, P＜0.001). Prevalence of CMD in low (NLR ≤ 1.53, n = 30), medium (1.53 < NLR ≤ 2.20, n = 53) and high (NLR > 2.20, n = 77) group were 90%, 61.1%, and 39.2% respectively. The prevalence of CMD significantly increased as NLR level decreased. After adjusting potential related factors, NLR was still significantly correlated with CMD (OR = 0.295, 95 %CI:0.162-0.539, P < 0.001). The area under ROC curve (AUC) was 0.707 (95 %CI:0.627-0.786, P < 0.001).

CONCLUSIONS

Our results showed that NLR is associated with CMD in T2DM patients, and the prevalence of CMD may increase as NLR level decrease.

miR‑130b regulates PTEN to activate the PI3K/Akt signaling pathway and attenuate oxidative stress‑induced injury in diabetic encephalopathy

Diabetic encephalopathy (DE) is one of the main chronic complications of diabetes, and is characterized by cognitive defects. MicroRNAs (miRNAs/miRs) are widely involved in the development of diabetes-related complications. The present study evaluated the role of miR-130b in DE and investigated its mechanisms of action. PC12 cells and hippocampal cells were exposed to a high glucose environment to induce cell injuries to mimic the in vitro model of DE. Cells were transfected with miR-130b mimic, miR-130b inhibitor and small interfering RNA (si)-phosphatase and tensin homolog (PTEN) to evaluate the protective effect of the miR-130b/PTEN axis against oxidative stress in high glucose-stimulated cells involving Akt activity. Furthermore, the effect of agomir-130b was also assessed on rats with DE. The expression of miR-130b was reduced in the DE models in vivo and in vitro. The administration of miR-130b mimic increased the viability of high glucose-stimulated cells, prevented apoptosis, increased the activity of superoxide dismutase (SOD), decreased the malondialdehyde (MDA) content, activated Akt protein levels and inhibited the mitochondria-mediated apoptotic pathway. The administration of miR-130b inhibitor exerted opposite effects, while si-PTEN reversed the effects of miR-130b inhibitor. In vivo, the administration of agomir-130b attenuated cognitive disorders and neuronal damage, increased SOD activity, reduced the MDA content, activated Akt protein levels and inhibited the mitochondria-mediated apoptosis pathway in rats with DE. On the whole, these results suggest that miR-130b activates the PI3K/Akt signaling pathway to exert protective effects against oxidative stress injury via the regulation of PTEN in rats with DE.

Palmatine Inhibits Up-Regulation of GRP78 and CALR Protein in an STZ-Induced Diabetic Rat Model

BACKGROUND

Diabetes Mellitus (DM) is characterized by hyperglycemia (high blood glucose levels) which is due to the destruction of insulin-producing β-cells in the islets of Langerhans in the pancreas. It is associated with oxidative and endoplasmic reticulum stress. The plant alkaloid Palmatine has been previously reported to possess antidiabetic and antioxidant properties as well as other protective properties against kidney and liver tissue damage.

OBJECTIVE

Here, we investigated the ability of Palmatine to reduce the up-regulation of chaperone proteins Glucose Regulatory Protein 78 (GRP78), and Calreticulin (CALR) protein in a Streptozotocin (STZ)-induced diabetic rat model.

METHODS

Streptozotocin (STZ) induced diabetes in Sprague Dawley rats treated with 2mg/kg of Palmatine for 12 weeks after the elevation of plasma glucose levels above 11mmol/L post-STZ administration. Proteins were extracted from the pancreas after treatment and Two-Dimensional gel electrophoresis (2-DE), PDQuest 2-D analysis software genomic solutions and mass spectrometer were used to analyze differentially expressed protein. Mass Spectrometry (MS/MS), Multidimensional Protein Identification Technology (MudPIT) was used for protein identification.

RESULTS

There was an up-regulation of the expression of chaperone proteins CALR and GRP78 and down-regulation of the expression of antioxidant and protection proteins peroxidoxin 4 (Prdx4), protein disulfide isomerase (PDIA2/3), Glutathione-S-Transferase (GSTs), and Serum Albumin (ALB) in non-diabetic rats. Palmatine treatment down-regulated the expression of chaperone proteins CALR and GRP78 and up-regulated the expression of Prdx4, PDIA2/3, GST, and ALB.

CONCLUSION

Palmatine may have activated antioxidant proteins, which protected the cells against reactive oxygen species and endoplasmic stress. The result is in consonance with our previous report on Palmatine.

The effect of Salaciareticulata, Syzygiumcumini, Artocarpusheterophyllus, and Cassiaauriculata on controlling the rapid formation of advanced glycation end-products

BACKGROUND

The excessive formation of Advanced Glycation End-products (AGEs) by non-enzymatic glycation mediates many health complications in the human body and the formation of AGEs largely accelerated under the hyperglycaemic condition.

OBJECTIVE

The prospect of the study to assess the strength of inhibiting the rapid AGE formations in four Ayurvedic medicinal plants, namely; Salacia reticulata (stems), Syzygium cumini (barks), Artocarpus heterophyllus (mature leaves) and, Cassia auriculata (flowers).

MATERIALS AND METHODS

Herbal decoctions of four medicinal plant materials were prepared by simmering with hot water as prescribed by the Ayurvedic medicine. The effectiveness of the decoctions was analyzed in vitro based on their Anti-AGE formation activity, glycation reversing, and anti-oxidant potentials.

RESULTS

According to the results, the decoctions of S. reticulata, A. heterophyllus and C. auriculata indicated the strong Anti-AGE forming (IC₅₀: 23.01 ± 2.70, 32.01 ± 2.09, 43.66 ± 2.11 mg/mL, respectively), glycation reversing (EC₅₀: 183.15 ± 7.67, 91.85 ± 1.93, 252.35 ± 4.03 mg/mL, respectively) and antioxidant potentials in terms of total polyphenol content (TPC), total flavonoid content (TFC), ferric ion reducing power (FRAP), ABTS and DPPH radical scavenging activities. However, the decoction of S. cumini reported the significantly high (p < 0.05) Anti-AGE forming, (IC₅₀: 9.75 ± 0.32 mg/mL), glycation reversing (EC₅₀: 66.45 ± 4.51 mg/mL), and antioxidant potentials against the decoctions of the other three plant materials.

CONCLUSION

S. cumini bark extract was identified as the best source in controlling the formation of AGEs excessively. Further, the other three plant extracts can also be effectively used as potential therapeutic agents to control the pathological conditions associated with AGEs-mediated health complications.

Vitamin A and Daucus carota root extract mitigate STZ-induced diabetic retinal degeneration in Wistar albino rats by modulating neurotransmission and downregulation of apoptotic pathways

The objective of our study was to explore the deleterious effects of diabetes on the visual functions of the retina and to address whether the administration of vitamin A and carrot root extract (CE) confer retinal protection in hyperglycemic rats via modulation of oxidative stress, biochemical alternations, and retinal neurotransmission. Fifty male Wistar albino rats weighing 180 ± 12.41 g were randomized into five groups (n = 10): controls, diabetic group (injected with 40 mg/kg dissolved in 0.1 sodium citrate buffer), diabetic group treated with vitamin A (2,500 IU/kg, low dose), diabetic group treated with vitamin (5,000 IU/kg, high dose), and diabetic groups administered CE (200 mg/kg/every other day). Our findings showed that, compared to controls, diabetic rats showed a significant decrease in their retinal thickness, increased apoptotic ganglion cells, and a noticeable degeneration of their synaptic layers. The inner retina displayed increased activity of neovascularization; however, the outer retina exhibited vacuolar degeneration of the photoreceptor cell layer. Our biochemical assessments showed reduced levels of CAT, SOD, and GST along with increased lipid peroxidation. Concurrently, cellular angiogenic and stress markers were significantly elevated associated with increased apoptotic activities as evidenced by increased expressions of annexin-V and PARP. Furthermore, the neurotransmitter content of the retina was altered in diabetic rats compared to controls and diabetic-treated groups. Paradoxically, vitamin A and CE supplementation attenuate these retinal insults in diabetic animals and normalized aforementioned assayed parameters; evidencing that both treatments exerted ameliorative impacts and restored visual functions by diminishing oxidative stress and neuronal degeneration. PRACTICAL APPLICATIONS: Diabetes is a complex disease that involves various physiological perturbations especially visual functions. In our study, we showed that vitamin A and carrot root extract (CE) confer remarkable protection against retinal degeneration in STZ-induced diabetic rats. Our findings showed that the chemical and phytochemical ingredients of the vitamin A and CE substantially attenuated the histopathological changes, oxidative stress, inflammatory reactions, and cellular death in diabetic rats. These favorable changes are attributable to the high content of retinoic acid, carotenoids, and phenolic compounds that effectively regulates the production of visual pigments, increases the antioxidant defense system, and diminishes the pro-inflammatory and apoptotic pathways. Thus, the nutritional values of vitamin A and CE represent promising therapeutic choices to mitigate the retinal-induced diabetic insults.

Taurine and oxidative stress in retinal health and disease

Retinal disorders are leading causes of blindness and are due to an imbalance between reactive oxygen species and antioxidant scavenger (in favor of pro‐oxidant species) or a disruption of redox signaling and control. Indeed, it is well known that oxidative stress is one of the leading causes of retinal degenerative diseases. Different approaches using nutraceuticals resulted in protective effects in these disorders. This review will discuss the impact of oxidative stress in retinal neurodegenerative diseases and the potential strategies for avoiding or counteracting oxidative damage in retinal tissues, with a specific focus on taurine. Increasing data indicate that taurine may be effective in slowing down the progression of degenerative retinal diseases, thus suggesting that taurine can be a promising candidate for the prevention or as adjuvant treatment of these diseases. The mechanism by which taurine supplementation acts is mainly related to the reduction of oxidative stress. In particular, it has been demonstrated to improve retinal reduced glutathione, malondialdehyde, superoxide dismutase, and catalase activities. Antiapoptotic effects are also involved; however, the protective mechanisms exerted by taurine against retinal damage remain to be further investigated.

Nephroprotective Effect of Adropinin Against Streptozotocin-Induced Diabetic Nephropathy in Rats: Inflammatory Mechanism and YAP/TAZ Factor

BACKGROUND

Diabetic Nephropathy remains a major cause of morbidity and mortality in patients suffering from renal dysfunction. This study accessed the nephroprotective role of Adropinin against streptozotocin (STZ) induced diabetic nephropathy in rats and scrutinizes the possible mechanism of action.

METHODS

STZ (45 mg/kg) dose was used for inducing diabetic nephropathy (DN) and rats were divided into different groups and received the dose-dependent treatment of Adropinin. Blood glucose level, body weight, tissue weight, antioxidant, renal, hepatic parameters, and cytokines were determined. At the end of the experimental study, renal histopathology was performed.

RESULTS

Adropinin significantly (P<0.001) boosted plasma insulin levels and reduced the blood glucose level. Adropinin considerably increased body weight and reduced kidney weight and kidney hypertrophy. Adropinin significantly (P<0.001) reduced urine outflow, microalbumin, total protein, blood urea nitrogen (BUN), uric acid and increased the creatinine, creatinine clearance. Adropinin significantly (P<0.001) reduced the indole sulfate level in the serum, kidney and reduced in the urine. Adropinin significantly (P<0.001) reduced the total cholesterol, triglyceride, low-density lipoprotein (LDL), very-low-density lipoprotein (VLDL) and increased the level of high-density lipoprotein (HDL). Adropinin significantly (P<0.001) increased the level of antioxidant enzymes such as glutathione (GSH), superoxide dismutase (SOD), catalase (CAT) and reduced the level of malonaldehyde (MDA), 8-hydroxy-2' -deoxyguanosine (8-OHdG). Adropinin significantly (P<0.001) reduced the level of interleukin-1β (IL-1β), interleukin-6 (IL-6), transforming growth factor beta (TGF-β) and increased the level of interleukin-10 (IL-10), respectively. Adropinin treatment showed improvement in renal histopathology.

CONCLUSION

We can say that Adropinin showed the nephroprotective effect against the STZ-induced diabetic nephropathy rats via inflammatory and antioxidant pathway.

Cardioprotective Activities of Ethanolic Extract Root of Ageratum conyzoides on Alloxan-Induced Cardiotoxicity in Diabetic Rats

Diabetes mellitus has developed into one of the debilitating diseases disturbing the health of many people living with cardiovascular diseases in modern times. The root of Ageratum conyzoides was investigated for its effects on alloxan-induced diabetic Wistar rats' cardiac tissues. Thirty-two (32) Wistar rats weighing between 180 and 190 g were randomly divided into four groups. The animals in groups B-D were induced with a single dose of 150 mg/kg body weight of alloxan (ALX) intraperitoneally. They were confirmed hyperglycemic after 72 hours of induction and then sustained in hyperglycemic condition for 2 weeks. Animals in groups C and D received AC intervention, as stated above, for four weeks. The body weight of the experimental animals and blood collection for glucose estimation were taken weekly for six weeks using appropriate instruments. Biochemical assays for lipid profile, antioxidant enzymatic, and nonenzymatic markers were carried out. Histopathological changes in the cardiac tissues were also studied. Administration of 150 mg/kg of ALX to experimental rats induced diabetes and significantly reduced the body weights, significantly (p < 0.05) increased the glucose level, triglyceride (TG), total cholesterol (TC), and low-density lipoprotein (LDL) levels, and decreased the levels of high-density lipoprotein (HDL) and antioxidant enzymatic markers such as catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) while the antioxidant nonenzymatic marker such as malondialdehyde (MDA) level was significantly increased. By contrast, rats given the ethanolic extract root of A. conyzoides had significantly (p < 0.05) increased the body weight gain, whereas the glucose levels significantly (p < 0.05) improved in treated diabetic rats. This extract also improved the cardiovascular system of the diabetic rats by significantly decreasing TG and LDL levels, significantly (p < 0.05) increasing the HDL level, significantly reducing the cardiac contents of CAT, SOD, and GPx, and significantly (p < 0.05) decreasing MDA. Ethanolic extract root of A. conyzoides exhibited antihyperglycemic and antihyperlipidemic activities and mitigates damage to the heart from the ALX-induced myocardial toxicity associated with type-1 diabetes.

Evaluation of efficacy of Bombax ceiba extract and its major constituent, mangiferin in streptozotocin (STZ)-induced diabetic rats

OBJECTIVES

Based on the ethno-medicinal use of Bombax ceiba leaf, in the treatment of diabetes, the present study is aimed at evaluation of antidiabetic potential of leaf extract and its major constituent mangiferin.

METHODS

Efficacy of hydroalcoholic extract of Bombax ceiba leaf (BCL, 200 and 400 mg/kg body wt.) and mangiferin (MF, 20 mg/kg body wt) was studied in streptozotocin (STZ)-induced diabetic rats and associated complications visually, retinopathy, cardiopathy and nephropathy. After 20 days, serum glucose, lipid profiles, glycol-hemoglobin % (HbA1c%), liver enzymes activity and glycogen content, and histopathology of the pancreas were corroborated. The study was coxswained for development of validated RP-HPLC method for the estimation of MF in BCL.

RESULTS

The results demonstrated significant reductions in the levels of glucose (p<0.001), glycated hemoglobin (HbA1c%, p<0.001), cholesterol, triglycerides and low-density lipoproteins, and concurrent elevation of high density lipoproteins level in the groups administered BCL and MF relative to the controls. It significantly reversed most of the altered metabolic and oxidative stress parameters and histopathological changes. Mangiferin content in BCL was found to be 0.04%w/w.

CONCLUSIONS

The anti-diabetic effects of BCL may be attributed to its ability to enhance insulin release, antioxidant and hypolipidemic potential.

Cyclocarya paliurus ethanol leaf extracts protect against diabetic cardiomyopathy in db/db mice via regulating PI3K/Akt/NF-κB signaling

Background

Diabetic cardiomyopathy (DCM) is a serious complication of diabetes that can lead to significant mortality. Cyclocarya paliurus is a tree, the leaves of which are often utilized to prevent and treat diabetes mellitus. Whether C. paliurus leaves can prevent or treat DCM, however, it remains to be formally assessed. The present study was therefore designed to assess the ability of C. paliurus to protect against DCM in db/db mice.

Methods

Male wild-type (WT) and db/db mice were administered C. paliurus ethanol leaf extracts (ECL) or appropriate vehicle controls daily via gavage, and levels of blood glucose in treated animals were assessed on a weekly basis. After a 10-week treatment, the levels of cardiac troponin I (cTn-I), lactate dehydrogenase (LDH), creatine kinase MB (CK-MB), aspartate transaminase (AST), total triglycerides (TG), and total cholesterol (TC) in serum were measured. Activities of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) and the levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and IL-6 in heart tissues were detected. Hematoxylin-eosin (HE) and Masson staining were conducted. The protein expression that related with oxidative stress and inflammatory reaction was evaluated by Western blotting.

Results

Compared with WT mice, the TG, TC, and blood glucose levels in db/db mice increased significantly, which were reduced by ECL treatment. Compared with WT mice, the levels of LDH, CK-MB, AST, and cTn-I in serum and MDA in heart tissues of db/db mice increased significantly. Activities of SOD, GSH-Px, and CAT in heart tissues of db/db mice decreased significantly. The levels of inflammatory cytokines (TNF-α, IL-1β, and IL-6) in heart tissues of db/db mice increased remarkably. However, ECL treatment improved the above pathological changes significantly. ECL alleviated pathological injury and fibrosis in heart tissues of mice. Western blotting showed that ECL increased Bcl-2 level and decreased Bax, cle-caspase-3, and cle-caspase-9 expression. Furthermore, ECL inhibited NF-κB nuclear translocation and increased PI3K and p-Akt expressions.

Conclusion

Our results indicate that ECL treatment can markedly reduce pathological cardiac damage in db/db mice through antiapoptotic, antifibrotic, and anti-inflammatory mechanisms. Specifically, this extract was able to suppress NF-κB activation via the PI3K/Akt signaling pathway. Given its diverse activities and lack of significant side effects, ECL may thus have therapeutic value for the treatment of DCM.

The molecular mechanisms associated with the physiological responses to inflammation and oxidative stress in cardiovascular diseases

The complex physiological signal transduction networks that respond to the dual challenges of inflammatory and oxidative stress are major factors that promote the development of cardiovascular pathologies. These signaling networks contribute to the development of age-related diseases, suggesting crosstalk between the development of aging and cardiovascular disease. Inhibition and/or attenuation of these signaling networks also delays the onset of disease. Therefore, a concept of targeting the signaling networks that are involved in inflammation and oxidative stress may represent a novel treatment paradigm for many types of heart disease. In this review, we discuss the molecular mechanisms associated with the physiological responses to inflammation and oxidative stress especially in heart failure with preserved ejection fraction and emphasize the nature of the crosstalk of these signaling processes as well as possible therapeutic implications for cardiovascular medicine.

Ergosterol ameliorates renal inflammatory responses in mice model of diabetic nephropathy

Ergosterol (ERG) was reported to exhibit anti-inflammatory and anti-oxidative activities. Besides, ERG was found to attenuate kidney injury in the diabetic mouse. However, the protective effect of ERG in diabetic nephropathy-induced inflammation remains unclear. We aimed to study whether ERG could alleviate diabetic nephropathy-induced inflammation and explore the underlying mechanisms. The diabetic nephropathy mice model was induced by intraperitoneal injection of 30 mg/kg Streptozotocin (STZ). The inflammatory cytokines levels, and insulin concentration in the serum of both diabetic nephropathy patients and mouse model were determined by ELISA. mRNA and protein expression were analyzed by RT-PCR and Western blot, respectively. Fasting blood glucose levels were detected using a commercial kit. Blood biochemistry levels were determined by an automatic analyzer. Mesangium proliferation was detected by PAS staining. It was found that serum levels of IL-6, TNF-α, and MCP-1 dramatically increased in the diabetic nephropathy patients. In mice, ERG treatment greatly decreased fasting blood glucose levels, inflammatory cytokine levels, and renal injury, while it enhanced the insulin level. Mechanically, ERG treatment dramatically decreased NF-κB signaling pathway. Our findings highlight the potential of ERG as an effective agent to treat diabetic nephropathy.

Quercetin ameliorates diabetic encephalopathy through SIRT1/ER stress pathway in db/db mice

Studies have shown that diabetes is an important risk factor for cognitive dysfunction, also called diabetic encephalopathy (DE). Quercetin has been reported to be effective in improving cognitive dysfunction in DE. But its detailed mechanism is still ambiguous. In this study, we used db/db mice to investigate whether quercetin could activate SIRT1 and inhibit ER pathways to improve DE. Behavioral tests (Morris water maze and new objects) showed that quercetin (70 mg/kg) can effectively improve the learning and memory ability in db/db mice. OGTT and ITT tests indicated that quercetin could alleviate impaired glucose tolerance and insulin resistance in db/db mice. Western blot analysis and Nissl staining showed that quercetin can improve the expression of nerve and synapse-associated proteins (PSD93, PSD95, NGF and BDNF) and inhibit neurodegeneration. Meanwhile, quercetin up-regulates SIRT1 protein expression and inhibits the expression of ER signaling pathway-related proteins (PERK, IRE-1α, ATF6, eIF2α, BIP and PDI). In addition, oxidative stress levels were significantly reduced after quercetin treatment. In conclusion, current experimental results indicated that SIRT1/ER stress is a promising mechanism involved in quercetin-treated diabetic encephalopathy.

The Influence of Light on Reactive Oxygen Species and NF-кB in Disease Progression

Reactive oxygen species (ROS) are important secondary metabolites that play major roles in signaling pathways, with their levels often used as analytical tools to investigate various cellular scenarios. They potentially damage genetic material and facilitate tumorigenesis by inhibiting certain tumor suppressors. In diabetic conditions, substantial levels of ROS stimulate oxidative stress through specialized precursors and enzymatic activity, while minimum levels are required for proper wound healing. Photobiomodulation (PBM) uses light to stimulate cellular mechanisms and facilitate the removal of oxidative stress. Photodynamic therapy (PDT) generates ROS to induce selective tumor destruction. The regulatory roles of PBM via crosstalk between ROS and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-кB) are substantial for the appropriate management of various conditions.

siRNA- and miRNA-based therapeutics for liver fibrosis

Liver fibrosis is a wound-healing process induced by chronic liver injuries, such as nonalcoholic steatohepatitis, hepatitis, alcohol abuse, and metal poisoning. The accumulation of excessive extracellular matrix (ECM) in the liver is a key characteristic of liver fibrosis. Activated hepatic stellate cells (HSCs) are the major producers of ECM and therefore play irreplaceably important roles during the progression of liver fibrosis. Liver fibrogenesis is highly correlated with the activation of HSCs, which is regulated by numerous profibrotic cytokines. Using RNA interference to downregulate these cytokines in activated HSCs is a promising strategy to reverse liver fibrosis. Meanwhile, microRNAs (miRNAs) have also been exploited for the treatment of liver fibrosis. This review focuses on the current siRNA- and miRNA-based liver fibrosis treatment strategies by targeting activated HSCs in the liver.

Crocin treatment decreased pancreatic atrophy, LOX-1 and RAGE mRNA expression of pancreas tissue in cholesterol-fed and streptozotocin-induced diabetic rats

Objective

Oxidative stress in diabetic mellitus is a consequence of oxidative stress, which plays a critical role in the pathogenesis of diabetic tissue damage. Receptors for advanced glycation end products and for oxidized low-density lipoproteins (LDL) have critical contribution in oxidative tissue damage. The present study investigated whether anti-diabetic effects of Crocin via modulation of mRNA expression of RAGE and LOX-1 receptors in diabetic rats.

Methods

In the current study, high-fat cholesterol (HFC) and streptozotocin (40 mg/kg) used to induce type II diabetes. Experimental groups as follows: (Group 1: control); (Group 2: control treatment [Crocin]); (Group 3: DM [STZ]); (Group 4: DM treatment [STZ + Crocin]); (Group 5; DM + HFC [STZ + HFC]); (Group 6; DM + HFC treatment [STZ + HFC + Crocin]). Crocin (20 mg/kg/day, i.p.) administered in treatment groups for 60 days. Serum glucose and cholesterol levels evaluated on days 5, 30 and 60 after induction of DM. Pancreatic tissue from all group removed on day 60 for histological and RT-PCR analysis.

Results

Application of Crocin significantly decreased serum cholesterol levels on day 60 after induction of DM in diabetic + HFC rats. Moreover, Crocin significantly decreased serum glucose levels on days 30 and 60 both in diabetic and diabetic + HFC rats. Crocin partially prevented the atrophic effects of STZ on both exocrine and endocrine parts of pancreas. Additionally, Crocin significantly decreased LOX-1 and RAGE mRNA expression OF pancreas in diabetic rats.

Conclusion

The current study suggested that Crocin suppressed atrophic change of the pancreas by decrease of LOX-1 and RAGE mRNA expression in diabetic rats.

Antihyperglycemic and antihyperlipidemic activities of a polysaccharide from Physalis pubescens L. in streptozotocin (STZ)-induced diabetic mice

In this study, a polysaccharide was extracted from Physalis pubescens L. (named PP). Its antihyperglycemic and antihyperlipidemic activities were evaluated in STZ-induced diabetic mice. Results showed that PP was determined to be composed of rhamnose (Rha), arabinose (Ara), fucose (Fuc), xylose (Xyl), mannose (Man), glucose (Glc) and galactose (Gal) with molar percentages of 4.65%, 17.34%, 1.43%, 6.24%, 5.52%, 45.5%, and 19.31%, respectively. The average molecular weight (Mw) was found to be 20.0 kDa. It had a strong α-glucosidase inhibitory activity in vitro. PP treatment could enhance the oral glucose tolerance, and increase the levels of SOD, GSH, CAT, vitamin C, vitamin E, HDL-c, C-peptide, GCK and hepatic glycogen in diabetic mice. Besides, PP treatment could also decrease the levels of MDA, TG, TC, LDL-c, BUN and G-6-Pase. The regulating effects were stronger in high dose PP treatment than those in the low and medium dose treatments. In short, PP played an important role in protecting STZ-induced diabetic mice, and the effect was closely related to its activities in antioxidation and regulating glucose and lipid metabolism.

Nepeta angustifolia attenuates responses to vascular inflammation in high glucose-induced human umbilical vein endothelial cells through heme oxygenase-1 induction

ETHNOPHARMACOLOGICAL RELEVANCE

The traditional folk medicine Nepeta angustifolia C. Y. Wu (NA) reportedly possesses various biological activities, such as anti-inflammatory, analgesic, antihypoxia, and antifatigue effects. In this study, we evaluated the anti-vascular inflammation effects of N. angustifolia extract in human umbilical vein endothelial cells (HUVECs) induced by high glucose (HG) as well as the underlying mechanisms and verified its activity in diabetic rats.

MATERIALS AND METHODS

HUVECs were exposed to 25 mM glucose to induce endothelial dysfunction. Adhesion molecule expression and reactive oxygen species (ROS) were assayed. IκB and IκB phosphorylation, nuclear factor-κB (NF-κB), HO-1 and nuclear factor erythroid 2-related factor 2 (Nrf2) were examined by Western blot. Nuclear localisation of Nrf2 was also examined using immunofluorescence. The in vivo study of NA was tested in diabetic rats in which the thoracic aorta and serum were collected to observe aorta histological change, and evaluate endothelial function and vascular inflammation.

RESULTS

The results revealed that HG can significantly promote the generation of ROS, the expression of cell adhesion molecules (CAMs), and the phosphorylation and degradation of IκB and NF-κB activation in HUVECs. These HG-induced phenomena were suppressed by NA-induced heme oxygenase (HO)- 1 expression in a dose- and time-dependent manner by activating Nrf2. The HO-1 inhibitor tin protoporphyrin also dramatically reversed the NA-induced inhibition of CAM expression and the reduction in ROS production. Furthermore, NA also elicited anti-vascular dysfunction effects in diabetic rats, where endothelial function was improved and vascular inflammation was alleviated.

CONCLUSION

All these findings indicated that NA attenuated high glucose-induced vascular dysfunction in vitro and in vivo.

Antidiabetic and Antioxidant Effects of Apple Cider Vinegar on Normal and Streptozotocin-Induced Diabetic Rats

Abstract. Diabetes mellitus (DM) is a globally growing health problem and one of the most prevalent endocrine disorders worldwide. Chronic hyperglycemia status favors the manifestation of oxidative stress by increasing the production of reactive oxygen species and/or by reducing the antioxidant defense system activity. In this study, the beneficial effects of apple cider vinegar (ACV) supplementation on blood glucose level, hepatic and renal toxicity and antioxidant enzyme activities in normal and diabetic rats were investigated. Four groups (8 animals/group) of male Wistar rats were used. The animals were fasted overnight and DM was induced by an intraperitoneal injection of freshly prepared streptozotocin (STZ). Control rats were injected with citrate buffer only. ACV was administrated orally for 4 weeks. Our findings indicated that ACV increased the activity of antioxidant enzymes (superoxide dismutase (p < 0.001), catalase and glutathione peroxidase) as well as thiol concentration (p < 0.05). It also reduced lipid peroxidation levels (TBARS) and the indices of toxicity in liver and kidneys, by significantly decreasing aspartate and lactate transaminase (AST & ALT) activity, total and direct bilirubin (p < 0.001), urea (p < 0.001) and creatinine (p < 0.001) levels. Moreover, the plasma concentration of magnesium, calcium (p < 0.001) and copper increased after ACV administration. Iron levels however decreased. The concentration of vitamin E, an important antioxidant in vivo, was raised. In conclusion, the findings show that ACV possesses significant antihyperglycemic and antioxidant effects in an experimental model of DM, by preventing diabetic complications in liver and kidneys.

Beneficial Effects of Resveratrol Administration-Focus on Potential Biochemical Mechanisms in Cardiovascular Conditions

Resveratrol (RV) is a natural non-flavonoid polyphenol and phytoalexin produced by a number of plants such as peanuts, grapes, red wine and berries. Numerous in vitro studies have shown promising results of resveratrol usage as antioxidant, antiplatelet or anti-inflammatory agent. Beneficial effects of resveratrol activity probably result from its ability to purify the body from ROS (reactive oxygen species), inhibition of COX (cyclooxygenase) and activation of many anti-inflammatory pathways. Administration of the polyphenol has a potential to slow down the development of CVD (cardiovascular disease) by influencing on certain risk factors such as development of diabetes or atherosclerosis. Resveratrol induced an increase in Sirtuin-1 level, which by disrupting the TLR4/NF-κB/STAT signal cascade (toll-like receptor 4/nuclear factor κ-light-chain enhancer of activated B cells/signal transducer and activator of transcription) reduces production of cytokines in activated microglia. Resveratrol caused an attenuation of macrophage/mast cell-derived pro-inflammatory factors such as PAF (platelet-activating factor), TNF-α (tumour necrosis factor-α and histamine. Endothelial and anti-oxidative effect of resveratrol may contribute to better outcomes in stroke management. By increasing BDNF (brain-derived neurotrophic factor) serum concentration and inducing NOS-3 (nitric oxide synthase-3) activity resveratrol may have possible therapeutical effects on cognitive impairments and dementias especially in those characterized by defective cerebrovascular blood flow.

Oxidative stress effects in the uterus, placenta and fetus of pregnant rats submitted to acute and chronic stress

PURPOSE

To evaluate the effects of oxidative stress in pregnant rats submitted to acute and chronic stress, relating to alterations in the uterus, placenta and fetus.

METHODS

Twenty-four female Wistar albino (Rattus norvegicus), were divided into four groups, for induction of oxidative stress the animals were submitted to cold and physical immobilization. Plasma fasting glucose and MDA were determined in all groups and the fetuses and placentas were measured.

RESULTS

There were no statistical differences in the levels of malonic dialdehyde (MDA), however the averages of chronic stress group were higher compared to control groups, which could explain the observed adverse effects; there was no correlation between puppies' size, the weight of the placenta and MDA values.

CONCLUSIONS

Chronic stress causes adverse effects, when compared to control groups; chronic stress group had fetuses, placentas and number of puppies, significantly lower compared to other groups. The rats exposed to chronic stress, also presented a higher frequency of fetal resorption.

The protective effect of betulinic acid (BA) diabetic nephropathy on streptozotocin (STZ)-induced diabetic rats

The present study was designed to investigate the protective effect of betulinic acid (BA) on streptozotocin (STZ)-induced diabetic rats. The rats were intraperitoneally injected with STZ (35 mg kg^-1). 7 days later, the animals were intragastrically administered with metformin (MET, 150 mg kg^-1), BA (20 mg kg^-1) or BA (40 mg kg^-1) once daily for consecutive 30 days. The blood glucose, the contents of insulin, interleukin-6 (IL-6), interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in serum were examined. The levels of IL-6, IL-1β, TNF-α, superoxide dismutase (SOD), catalase (CAT) and malondialdehyde (MDA) in kidney tissues were measured. Moreover, the histopathological alteration and the protein expressions of the signaling pathway were detected by hematoxylin and eosin (H&E) staining and western blotting, respectively. BA significantly decreased the levels of serum insulin, IL-6, IL-1β, TNF-α and blood glucose. In addition, BA increased the activities of SOD, CAT and reduced the contents of MDA, IL-6, IL-1β, and TNF-α in kidney tissues. BA also ameliorated the histopathological condition. Furthermore, BA attenuated the phosphorylations of p-adenosine 5'-monophosphate-activated protein kinase (AMPK), nuclear factor kappaB (NF-κB), and an inhibitor of NF-κB (IκBα) and the expressions of NF-E2-related factor 2 (Nrf2) and heme oxygenase (HO)-1. These findings demonstrated that BA exhibited a protective effect on diabetic nephropathy in STZ-induced rats possibly through the AMPK/NF-κB/Nrf2 pathway.

Oxidative stress: role of physical exercise and antioxidant nutraceuticals in adulthood and aging

Physical exercise is considered to be one of the beneficial factors of a proper lifestyle and is nowadays seen as an indispensable element for good health, able to lower the risk of disorders of the cardiovascular, endocrine and osteomuscular apparatus, immune system diseases and the onset of potential neoplasms. A moderate and programmed physical exercise has often been reported to be therapeutic both in the adulthood and in aging, since capable to promote fitness. Regular exercise alleviates the negative effects caused by free radicals and offers many health benefits, including reduced risk of all-cause mortality, sarcopenia in the skeletal muscle, chronic disease, and premature death in elderly people. However, physical performance is also known to induce oxidative stress, inflammation, and muscle fatigue. Many efforts have been carried out to identify micronutrients and natural compounds, also known as nutraceuticals, able to prevent or attenuate the exercise-induced oxidative stress and inflammation. The aim of this review is to discuss the benefits deriving from a constant physical activity and by the intake of antioxidant compounds to protect the body from oxidative stress. The attention will be focused mainly on three natural antioxidants, which are quercetin, resveratrol and curcumin. Their properties and activity will be described, as well as their benefits on physical activity and on aging, which is expected to increase through the years and can get favorable benefits from a constant exercise activity.

Reappraisal of metallothionein: Clinical implications for patients with diabetes mellitus

Reactive oxygen and nitrogen species (ROS and RNS, respectively) are byproducts of cellular physiological processes of the metabolism of intermediary nutrients. Although physiological defense mechanisms readily convert these species into water or urea, an improper balance between their production and removal leads to oxidative stress (OS), which is harmful to cellular components. This OS may result in uncontrolled growth or, ultimately, cell death. In addition, ROS and RNS are closely related to the development of diabetes and its complications. Therefore, numerous researchers have proposed the development of strategies for the removal of ROS/RNS to prevent or treat diabetes and its complications. Some molecules that are synthesized in the body or obtained from food participate in the removal and neutralization of ROS and RNS. Metallothionein, a cysteine-rich protein, is a metal-binding protein that has a wide range of functions in cellular homeostasis and immunity. Metallothionein can be induced by a variety of conditions, including zinc supplementation, and plays a crucial role in mediating anti-OS, anti-apoptotic, detoxification, and anti-inflammatory effects. Metallothionein can modulate various stress-induced signaling pathways (mitogen-activated protein kinase, Wnt, nuclear factor-κB, phosphatidylinositol 3-kinase, sirtuin 1/AMP-activated protein kinase and fibroblast growth factor 21) to alleviate diabetes and diabetic complications. However, a deeper understanding of the functional, biochemical, and molecular characteristics of metallothionein is needed to bring about new opportunities for OS therapy. This review focuses on newly proposed functions of a metallothionein and their implications relevant to diabetes and its complications.

The characterization, renoprotection and antioxidation of enzymatic and acidic exopolysaccharides from Hypsizigus marmoreus

The present work was designed to investigate the characterization, as well as the antioxidation and renoprotection in streptozocin (STZ)-induced diabetic mice, of exopolysaccharides (EPS) and the enzymatic-EPS (EEPS) and acidic-EPS (AEPS) hydrolysates, which were separated from the fermentation liquor of Hypsizigus marmoreus. Animal results demonstrated that EPS, EEPS and AEPS had potential antioxidant and renoprotective effects, especially EEPS. Additionally, they were the most effective, reflecting increases in superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT), total antioxidant capacity (T-AOC), and albumin (ALB) of 168.33%, 124.8%, 268.17% 179.49%, and 68.71%, respectively, and decreases in the contents of malondialdehyde (MDA), lipid peroxide (LPO) and levels of serum urea nitrogen (BUN) and creatinine (CRE) by 70.58%, 58.43%, 23.97% and 29.60%, respectively, at a dose of 800 mg/kg compared to those of model mice. Three polysaccharides ameliorated the histopathological alterations which were observed in the kidney of diabetic mice. Furthermore, the characterization of polysaccharides had been expressed. These findings indicated that the EEPS from H. marmoreus possesses more effective renoprotection and antioxidation effects and provided insight into its potential clinical values on preventing diabetes.

The effects of green cardamom supplementation on blood glucose, lipids profile, oxidative stress, sirtuin-1 and irisin in type 2 diabetic patients: a study protocol for a randomized placebo-controlled clinical trial

BACKGROUND

It has been suggested that the antioxidant, anti-inflammatory and hypolipidemic activities of cardamom may improve diabetes. However, the effect of this spice has not been investigated in diabetic subjects. This study was planned to determine the effects of green cardamom on blood glucose, lipids and oxidative stress status in type 2 diabetic patients.

METHODS/DESIGN

Eighty overweight or obese patients with type 2 diabetes will be selected. They will be randomly assigned to receive 3 g/d green cardamom or placebo for 10 weeks. The socio demographic, physical activity and 24-h food recall questionnaires will be collected for each subject. Weight, height and waist circumference will be measured. Determination of blood glucose, lipid profile, and oxidative stress biomarkers including serum levels of total antioxidant capacity (TAC), malondialdehyde (MDA), and glutathione peroxidase (GPx) and superoxide dismutase (SOD) in red blood cells will be performed. The homeostasis model assessment-estimated insulin resistance (HOMA-IR) index and the quantitative insulin-sensitivity check index (QUICKI) will be calculated. Also, serum levels of irisin, and Sirtuin1 (SIRT1) will be measured.

DISCUSSION

This trial will be the first study to explore the effects of green cardamom supplementation on glycemic control, lipid profile and oxidative stress in patients with type 2 diabetes mellitus. The results from this trial will provide evidence on the efficacy of green cardamom in type 2 diabetes mellitus.

TRIAL REGISTRATION NUMBER

( http://www.irct.ir , identifier: IRCT2016042717254N5), Registration date: 23.11.2016.

Advanced glycation end products induce neural tube defects through elevating oxidative stress in mice

Our previous study showed an association between advanced glycation end products (AGEs) and neural tube defects (NTDs). To understand the molecular mechanisms underlying the effect of AGEs on neural tube development, C57BL/6 female mice were fed for 4 weeks with commercial food containing 3% advanced glycation end product bovine serum albumin (AGE-BSA) or 3% bovine serum albumin (BSA) as a control. After mating mice, oxidative stress markers including malondialdehyde and H₂O₂ were measured at embryonic day 7.5 (E7.5) of gestation, and the level of intracellular reactive oxygen species (ROS) in embryonic cells was determined at E8.5. In addition to evaluating NTDs, an enzyme-linked immunosorbent assay was used to determine the effect of embryonic protein administration on the N-(carboxymethyl) lysine reactivity of acid and carboxyethyl lysine antibodies at E10.5. The results showed a remarkable increase in the incidence of NTDs at E10.5 in embryos of mice fed with AGE-BSA (no hyperglycemia) compared with control mice. Moreover, embryonic protein administration resulted in a noticeable increase in the reactivity of N-(carboxymethyl) lysine and N(ε)-(carboxyethyl) lysine antibodies. Malondialdehyde and H₂O₂ levels in embryonic cells were increased at E7.5, followed by increased intracellular ROS levels at E8.5. Vitamin E supplementation could partially recover these phenomena. Collectively, these results suggest that AGE-BSA could induce NTDs in the absence of hyperglycemia by an underlying mechanism that is at least partially associated with its capacity to increase embryonic oxidative stress levels.

NF-κβ: A Potential Target in the Management of Vascular Complications of Diabetes

Diabetes is a metabolic disorder affecting large percentage of population worldwide. NF-κβ plays key role in pathogenesis of vascular complications of diabetes. Persistent hyperglycemia activates NF-κβ that triggers expression of various cytokines, chemokines and cell adhesion molecules. Over-expression of TNF-α, interleukins, TGF-β, Bcl2 and other pro-inflammatory proteins and pro-apoptotic genes by NF-κβ is key risk factor in vascular dysfunction. NF-κβ over-expression also triggers calcification of endothelial cells leading to endothelial dysfunction and further vascular complications. Inhibition of NF-κβ pro-inflammatory pathway is upcoming novel target for management of vascular complications of diabetes. Various natural and synthetic inhibitors of NF-κβ have been studied in management of diabetic complications. Recent preclinical and clinical studies validate NF-κβ as promising target in the management of vascular complications of diabetes.