Cardioprotective effect of pioglitazone in diabetic and non-diabetic rats subjected to acute myocardial infarction involves suppression of AGE-RAGE axis and inhibition of apoptosis

Topiramate affords neuroprotection in diabetic neuropathy model via downregulating spinal GFAP/inflammatory burden and improving neurofilament production

The current study aimed to test the neuroprotective action of topiramate in mouse peripheral diabetic neuropathy (DN) and explored some mechanisms underlying this action. Mice were assigned as vehicle group, DN group, DN + topiramate 10-mg/kg and DN + topiramate 30-mg/kg. Mice were tested for allodynia and hyperalgesia and then spinal cord and sciatic nerves specimens were examined microscopically and neurofilament heavy chain (NEFH) immunostaining was performed. Results indicated that DN mice had lower the hotplate latency time (0.46-fold of latency to licking) and lower von-Frey test pain threshold (0.6-fold of filament size) while treatment with topiramate increased these values significantly. Sciatic nerves from DN control mice showed axonal degeneration while spinal cords showed elevated GFAP (5.6-fold) and inflammatory cytokines (∼3- to 4-fold) but lower plasticity as indicated by GAP-43 (0.25-fold). Topiramate produced neuroprotection and suppressed spinal cord GFAP/inflammation but enhanced GAP-43. This study reinforces topiramate as neuroprotection and explained some mechanisms included in alleviating neuropathy.

Network-pharmacology-based research on protective effects and underlying mechanism of Shuxin decoction against myocardial ischemia/reperfusion injury with diabetes

BACKGROUND

Patients with diabetes mellitus are at higher risk of myocardial ischemia/ reperfusion injury (MI/RI). Shuxin decoction (SXT) is a proven recipe modi-fication from the classic herbal formula "Wu-tou-chi-shi-zhi-wan" according to the traditional Chinese medicine theory. It has been successfully used to alleviate secondary MI/RI in patients with diabetes mellitus in the clinical setting. However, the underlying mechanism is still unclear.

AIM

To further determine the mechanism of SXT in attenuating MI/RI associated with diabetes.

METHODS

This paper presents an ensemble model combining network pharmacology and biology. The Traditional Chinese Medicine System Pharmacology Database was accessed to select key components and potential targets of the SXT. In parallel, therapeutic targets associated with MI/RI in patients with diabetes were screened from various databases including Gene Expression Omnibus, DisGeNet, Genecards, Drugbank, OMIM, and PharmGKB. The potential targets of SXT and the therapeutic targets related to MI/RI in patients with diabetes were intersected and subjected to bioinformatics analysis using the Database for Annotation, Visualization and Integrated Discovery. The major results of bioinformatics analysis were subsequently validated by animal experiments.

RESULTS

According to the hypothesis derived from bioinformatics analysis, SXT could possibly ameliorate lipid metabolism disorders and exert anti-apoptotic effects in MI/RI associated with diabetes by reducing oxidized low density lipoprotein (LDL) and inhibiting the advanced glycation end products (AGE)-receptor for AGE (RAGE) signaling pathway. Subsequent animal experiments confirmed the hypothesis. The treatment with a dose of SXT (2.8 g/kg/d) resulted in a reduction in oxidized LDL, AGEs, and RAGE, and regulated the level of blood lipids. Besides, the expression of apoptosis-related proteins such as Bax and cleaved caspase 3 was down-regulated, whereas Bcl-2 expression was up-regulated. The findings indicated that SXT could inhibit myocardial apoptosis and improve cardiac function in MI/RI in diabetic rats.

CONCLUSION

This study indicated the active components and underlying molecular therapeutic mechanisms of SXT in MI/RI with diabetes. Moreover, animal experiments verified that SXT could regulate the level of blood lipids, alleviate cardiomyocyte apoptosis, and improve cardiac function through the AGE-RAGE signaling pathway.

Synthesis, in-Silico studies and biological evaluation of pyrimidine based thiazolidinedione derivatives as potential anti-diabetic agent

Despite the advancements in the management of Diabetes mellitus, the design and synthesis of drug molecule which ameliorates the hyperglycemia and associated secondary complications in diabetic patients, still remains a challenge. Herein, we report the synthesis, characterization and anti-diabetic evaluation of pyrimidine-thiazolidinedione derivatives. The synthesized compounds were characterized by 1H NMR, 13C NMR, FTIR and Mass Spectroscopic analytical techniques. The in-silico ADME studies depicted that the compounds were within the permissible limits of the Lipinski's rule of five. The compounds 6e and 6m showing the best results in OGTT were evaluated for in-vivo anti-diabetic evaluation in STZ induced diabetic rats. Administration of 6e and 6m for four weeks decreased the blood glucose levels significantly. Compound 6e (4.5 mg/kg p.o.) was the most potent compound of the series. It reduced the level of blood glucose to 145.2 ± 1.35 compared to the standard Pioglitazone (150.2 ± 1.06). Moreover, the 6e and 6m treated group did not show increase in bodyweight. The biochemical estimations showed that the levels of ALT, ASP, ALP, urea, creatinine, blood urea nitrogen, total protein and LDH restored to normal in 6e and 6m treated groups as compared to STZ control group. The histopathological studies supported the results obtained in biochemical estimations. Both the compounds did not show any toxicity. Moreover, the histopathological studies of pancreas, liver, heart and kidney revealed that the structural integrity of these tissues restored to almost normal in 6e and 6m treated groups as compared to STZ control group. Based upon these findings it can be concluded that the pyrimidine-based thiazolidinedione derivatives represent novel anti-diabetic agents with least side effects.

Cardioprotective Effect of Flibanserin against Isoproterenol-Induced Myocardial Infarction in Female Rats: Role of Cardiac 5-HT2A Receptor Gene/5-HT/Ca2+ Pathway

Myocardial infarction (MI) is a life-threatening ischemic disease and is one of the leading causes of morbidity and mortality worldwide. Serotonin (5-HT) release during myocardial ischemia plays an important role in the progression of myocardial cellular injury. This study was conducted to investigate the possible cardioprotective effect of flibanserin (FLP) against isoproterenol (ISO)-induced MI in rats. Rats were randomly divided into five groups and were treated orally (p.o.) with FLP (15, 30, and 45 mg/kg) for 28 days. ISO was administered subcutaneously (S.C.) (85 mg/kg) on the 27th and 28th days to induce MI. ISO-induced myocardial infarcted rats exhibited a significant increase in cardiac markers, oxidative stress markers, cardiac and serum 5-HT levels, and total cardiac calcium (Ca2+) concentration. ISO-induced myocardial infarcted rats also revealed a remarkable alteration of electrocardiogram (ECG) pattern and significantly upregulated expression of the 5-Hydroxytryptamine 2A (5-HT2A) receptors gene. Moreover, ISO-induced myocardial infarcted rats showed significant histopathological findings of MI and hypertrophic signs. However, pretreatment with FLP significantly attenuated the ISO-induced MI in a dose-dependent manner, as the effect of FLP (45 mg/kg) was more pronounced than that of the other two doses, FLP (15 and 30 mg/kg). The present study provides evidence for the cardioprotective efficacy of FLP against ISO-induced MI in rats.

Characterization, antibacterial, antioxidant, antidiabetic, and anti-inflammatory activities of green synthesized silver nanoparticles using Phragmanthera austroarabica A. G. Mill and J. A. Nyberg extract

Introduction

Diabetes mellitus is a chronic metabolic disorder that exhibited great expansion all over the world. It is becoming an epidemic disease adding a major burden to the health care system, particularly in developing countries.

Methods

The plant under investigation in the current study Phragmanthera austroarabica A. G. Mill and J. A. Nyberg is traditionally used in Saudi Arabia for the treatment of diabetes mellitus. The methanolic extract (200 mg/kg) of the plant and pure gallic acid (40 mg/kg), a major metabolite of the plant, as well as their silver nanoparticle formulae (AgNPs) were evaluated for their antidiabetic activity.

Results and Discussion

The results showed a decrease in body fat, obesity, an improvement in lipid profiles, normalization of hyperglycemia, insulin resistance, and hyperinsulinemia, and an improvement in liver tissue structure and function. However, the results obtained from AgNPs for both extract and the pure gallic acid were better in most measured parameters. Additionally, the activity of both the crude extract of the plant and its AgNPs were evaluated against a number of gram-positive, gram-negative bacteria and fungi. Although the activity of the crude extract ranged from moderate to weak or even non-active, the AgNPs of the plant extract clearly enhanced the antimicrobial activity. AgNPs of the extract demonstrated remarkable activity, especially against the Gram-negative pathogens Proteus vulgaris (MIC 2.5 μg/ml) and Pseudomonas aeruginosa (MIC 5 μg/ml). Furthermore, a promising antimicrobial activity was shown against the Gram-positive pathogen Streptococcus mutants (MIC 1.25 μg/ml).

Interaction of Cardiovascular Nonmodifiable Risk Factors, Comorbidities and Comedications With Ischemia/Reperfusion Injury and Cardioprotection by Pharmacological Treatments and Ischemic Conditioning

Preconditioning, postconditioning, and remote conditioning of the myocardium enhance the ability of the heart to withstand a prolonged ischemia/reperfusion insult and the potential to provide novel therapeutic paradigms for cardioprotection. While many signaling pathways leading to endogenous cardioprotection have been elucidated in experimental studies over the past 30 years, no cardioprotective drug is on the market yet for that indication. One likely major reason for this failure to translate cardioprotection into patient benefit is the lack of rigorous and systematic preclinical evaluation of promising cardioprotective therapies prior to their clinical evaluation, since ischemic heart disease in humans is a complex disorder caused by or associated with cardiovascular risk factors and comorbidities. These risk factors and comorbidities induce fundamental alterations in cellular signaling cascades that affect the development of ischemia/reperfusion injury and responses to cardioprotective interventions. Moreover, some of the medications used to treat these comorbidities may impact on cardioprotection by again modifying cellular signaling pathways. The aim of this article is to review the recent evidence that cardiovascular risk factors as well as comorbidities and their medications may modify the response to cardioprotective interventions. We emphasize the critical need for taking into account the presence of cardiovascular risk factors as well as comorbidities and their concomitant medications when designing preclinical studies for the identification and validation of cardioprotective drug targets and clinical studies. This will hopefully maximize the success rate of developing rational approaches to effective cardioprotective therapies for the majority of patients with multiple comorbidities. SIGNIFICANCE STATEMENT: Ischemic heart disease is a major cause of mortality; however, there are still no cardioprotective drugs on the market. Most studies on cardioprotection have been undertaken in animal models of ischemia/reperfusion in the absence of comorbidities; however, ischemic heart disease develops with other systemic disorders (e.g., hypertension, hyperlipidemia, diabetes, atherosclerosis). Here we focus on the preclinical and clinical evidence showing how these comorbidities and their routine medications affect ischemia/reperfusion injury and interfere with cardioprotective strategies.

Prophylactic and Ameliorative Effects of PPAR-γ Agonist Pioglitazone in Improving Oxidative Stress, Germ Cell Apoptosis and Inflammation in Gentamycin-Induced Testicular Damage in Adult Male Albino Rats

Peroxisome proliferator-activated receptor gamma (PPAR-γ) is ubiquitously expressed in testicular tissue and plays a crucial role in regulating various physiological processes. Pioglitazone (PIO) is one of the PPAR-γ agonists, having anti-oxidant and anti-inflammatory effects. Patients on gentamycin treatment may undergo serious side effects such as testicular damage. To the best of our knowledge, this was the first study to investigate the possible protective anti-inflammatory and anti-apoptotic effects of PIO on gentamycin-induced testicular damage. Fifty adult male Wistar albino rats included in the study as the control group (CTL) received normal saline; a gentamycin-induced testicular damage group (GM) received gentamycin (100 mg/kg); PIO5, PIO10, PIO20 groups received PIO at a dose of 5, 10, and 20 mg/ kg, respectively, for 21 days, and gentamycin was started at day 15 of the experiment for 6 days. The parameters of spermatozoa and histopathological alterations in the testes were significantly improved in the PIO20 group. Moreover, MDA levels, inflammatory mediators, and apoptotic Bax expression were decreased. The activity of glutathione peroxidase, catalase, total antioxidant capacity, and anti-apoptotic Bcl-2 genes expression were increased. It was concluded that PIO20 could protect against gentamycin-induced testicular damage in Wistar rats through its anti-oxidant, anti-inflammatory, and antiapoptotic effects.

Cellular mechanisms and recommended drug-based therapeutic options in diabetic cardiomyopathy

Diabetes mellitus (DM) is associated with a specific cardiac phenotype characterized by structural and functional alterations. This so-called diabetic cardiomyopathy (DM CM) is clinically relevant as patients with DM show high incidence of heart failure. Mechanistically, several parameters interact on the cardiomyocyte level leading to increased inflammation, apoptosis, reactive oxygen species and altered calcium signaling. This in turn provokes functional myocardial changes that might inter alia play into the worsened clinical outcome in DM patients. Therefore, efficient therapeutic options are urgently needed. This review focuses on mechanistic effects of currently recommended antidiabetic treatment and heart failure therapy for DM CM.

Differential Effect of Three Macrolide Antibiotics on Cardiac Pathology and Electrophysiology in a Myocardial Infarction Rat Model: Influence on Sodium Nav1.5 Channel Expression

Macrolides were reported to have cardiotoxic effects presented mainly by electrocardiogram (ECG) changes with increased risk in cardiac patients. We aimed to determine the impact of three macrolides, azithromycin, clarithromycin and erythromycin, on cardiac electrophysiology, cardiac enzyme activities, histopathological changes, and sodium voltage-gated alpha subunit 5 (Nav1.5) channel expression. We used eight experimental groups of male albino rats: vehicle, azithromycin (100 mg/kg), clarithromycin (100 mg/kg), erythromycin (100 mg/kg), MI + vehicle, MI + azithromycin (100 mg/kg), MI + clarithromycin (100 mg/kg) and MI + erythromycin (100 mg/kg); each group received chronic oral doses of the vehicle/drugs for seven weeks. ECG abnormalities and elevated serum cardiac enzymes were observed particularly in rats with AMI compared to healthy rats. Microscopic examination revealed elevated pathology scores for rats treated with clarithromycin in both experiments following treatment with erythromycin in healthy rats. Although rats with MI did not show further elevations in fibrosis score on treatment with macrolides, they produced significant fibrosis in healthy rats. Downregulation of cardiac Nav1.5 transcript was observed following macrolides treatment in both groups (healthy rats and rats with MI). In conclusion, the current findings suggested the potential cardiotoxic effects of chronic doses of macrolide antibiotics in rats with MI as manifested by abnormal ECG changes and pathological findings in addition to downregulation of Nav1.5 channels. Furthermore, in the current dose ranges, azithromycin produced the least toxicity compared to clarithromycin and erythromycin.

Effect of Pioglitazone on endoplasmic reticulum stress regarding in situ perfusion rat model

BACKGROUND

Ischemia-reperfusion injury (IRI) can cause insufficient microcirculation of the transplanted organ and results in a diminished and inferior graft survival rate.

OBJECTIVE

This study aimed to investigate the effect of different doses of an anti-diabetic drug, Pioglitazone (Pio), on endoplasmic reticulum stress and histopathological changes, using an in situ perfusion rat model.

METHODS

Sixty male Wistar rats were used and were divided into six groups, consisting of the control group, vehicle-treated group and four Pio-treated groups (10, 20, 30 and 40 mg/kg Pio was administered). The rats were perfused through vena cava and an outflow on the abdominal aorta occurred. Following the experiment, kidneys and livers were collected. The level of the endoplasmic reticulum stress markers (XBP1 and Caspase 12) was analyzed using Western blot and histopathological changes were evaluated.

RESULTS

Histopathological findings were correlated with the Western blot results and depict a protective effect corresponding to the elevated dosage of Pioglitazone regarding in situ perfusion rat model.

CONCLUSIONS

In our study, Pioglitazone can reduce the endoplasmic reticulum stress, and the most effective dosage proved to be the 40 mg/kg Pio referencing the kidney and liver samples.

Role of sodium glucose cotransporter type 2 inhibitors dapagliflozin on diabetic nephropathy in rats; Inflammation, angiogenesis and apoptosis

AIMS

Diabetic nephropathy is a major cause of chronic kidney disease and end-stage renal failure worldwide. Dapagliflozin Sodium-glucose co-transporter 2 (SGLT2) inhibitor is a new class of diabetic medications prescribed for the treatment of type 2 diabetes. The current study investigates the possible impact of dapagliflozin (DAPA) on inflammations, apoptosis, angiogenesis and fibrosis in early-stage diabetic nephropathy using a rat model of type 2 diabetes.

MAIN METHODS

Rats were divided into five groups, group1: normal vehicle group, group 2: diabetic group, group 3: diabetic+ DAPA (0.75 mg/kg), group 4: diabetic+DAPA (1.5 mg/kg), group 5: diabetic+DAPA (3 mg/kg). At the end of the study, Blood glucose level was measured. Serum insulin, BUN, and SCr were measured. Insulin resistance was determined using the homeostasis model assessment for insulin resistance (HOMA-IR) index. Renal tissue homogenization was done for assessment of inflammatory markers TNF-α, PEDF, and PTX-3, In addition to apoptosis markers BCL-2 and BAX. Histopathological examinations were done for tubular renal cells and immunohistochemical examination for fibrosis marker α-SMA and angiogenic factor VEGF.

KEY FINDINGS

Treatments with dapagliflozin showed improvements in histopathological examinations, inflammatory and apoptotic markers compared to diabetic vehicles in a dose-dependent manner.

SIGNIFICANCE

Thus, dapagliflozin may have renoprotective effects, which be promising in diabetic patients suffered from nephropathy.

Early effect of laser irradiation in signaling pathways of diabetic rat submandibular salivary glands

Low-power laser irradiation (LPLI) is clinically used to modulate inflammation, proliferation and apoptosis. However, its molecular mechanisms are still not fully understood. This study aimed to describe the effects of LPLI upon inflammatory, apoptotic and proliferation markers in submandibular salivary glands (SMGs) in an experimental model of chronic disorder, 24h after one time irradiation. Diabetes was induced in rats by the injection of streptozotocin. After 29 days, these animals were treated with LPLI in the SMG area, and euthanized 24h after this irradiation. Treatment with LPLI significantly decreased diabetes-induced high mobility group box 1 (HMGB1) and tumor necrosis factor alpha (TNF-α) expression, while enhancing the activation of the transcriptional factor cAMP response element binding (CREB) protein. LPLI also reduced the expression of bax, a mitochondrial apoptotic marker, favoring the cell survival. These findings suggest that LPLI can hamper the state of chronic inflammation and favor homeostasis in diabetic rats SMGs.

Clopidogrel or prasugrel reduces mortality and lessens cardiovascular damage from acute myocardial infarction in hypercholesterolemic male rats

AIMS

Hypercholesterolemia is a hazard for increasing susceptibility of the heart to myocardial infarction (MI) by inducing platelet hyperaggregability. Clopidogrel and prasugrel have documented cardioprotective effects in clinical studies. Herein, we investigated whether clopidogrel and prasugrel could protect against isoproterenol-induced acute MI (A-MI) under hypercholesterolemic conditions in rats.

MAIN METHODS

Dietary hypercholesterolemic rats were subjected to acute doses of isoproterenol. Serum lipids, inflammatory markers, aortic endothelin1 and endothelial nitric oxide synthase (eNOS) mRNAs expression and immunexpression of BCL2 were determined.

KEY FINDINGS

Hypercholesterolemic rats showed infiltration of inflammatory cells and reduction in aortic wall thickness, deposition of fibrous tissue between cardiac muscle fibers. Protective doses of prasugrel or clopidogrel for 28 days before A-MI increased survival, amended the ECG parameters -including ST segment elevation- and improved the histopathological picture in hypercholesterolemic rats. This was coupled with reductions in platelet aggregation, creatine kinase-MB activity, endothelin 1, systemic inflammation and cardiac lipid peroxidation and increment in aortic eNOS expression. Clopidogrel and prasugrel groups showed enhanced BCL2 expression in cardiac fibers and aortic wall.

SIGNIFICANCE

Prasugrel and clopidogrel protected against A-MI via anti-aggregatory and anti-inflammatory effects. These results add to the value of these drugs in correcting cardiovascular dysfunction in patients vulnerable to A-MI after confirmation by appropriate human studies.

Pioglitazone attenuates advanced glycation end products-induced apoptosis and calcification by modulating autophagy in tendon-derived stem cells

Diabetes mellitus (DM) is one of the prominent risk factors for pathological development and progression of tendinopathy. One feature of DM-related changes in tendinopathy is accumulation of advanced glycation end products (AGEs) in affected tendons. Pioglitazone (Pio), a peroxisome proliferator-activated receptor γ agonist, performs a protective effect against AGEs. The present study aimed to investigate the pathogenetic role of AGEs on tendon-derived stem cells (TDSCs) and to determine the effect of Pio on AGEs-induced TDSC dysfunctions. Results indicated that AGEs induced TDSC apoptosis as well as compensatory activation of autophagy. Pharmacologic activation/inhibition of autophagy leaded to alleviate/exacerbate apoptosis induced by AGEs. We further confirmed the effect of Pio on autophagy, which ameliorated apoptosis and abnormal calcification caused by AGEs both in vitro and in vivo. Thus, we suggest that Pio ameliorates the dysfunctions of TDSCs against AGEs by promoting autophagy, and we also reveal that Pio is a potential pharmacological choice for tendinopathy.

Rubia tinctorum root extracts: chemical profile and management of type II diabetes mellitus

The chemical and biological profiling of the root extracts of Rubia tinctorum was performed. The activities of different extracts were determined considering the antidiabetic effect against type II diabetes mellitus together with anti-obesity and hepatoprotective effects and lipid profile. The methanolic extract of Rubia tinctorum exhibited significant results in decreasing body weight, improving lipid profile, normalizing hyperglycaemia, insulin resistance, hyperinsulinemia. Additionally, it showed enhancement of liver tissue structure and function. The methanolic extract, being the most significant one, was subjected to LC-HRMS analysis to determine its chemical constituents. Finally, the chemical constituents were evaluated by molecular docking study that was carried out to identify the interaction of a panel of 45 compounds in silico and to correlate the structures to their anti-diabetic activity. Among the tested compounds, 1-hydroxy-2-hydroxymethyl anthra-quinone and naringenin-7-O-glucoside showed the most potent activity as α-amylase inhibitors.

The chemical and biological profiling of the root extracts of Rubia tinctorum was performed.

Pioglitazone treatment prior to transplantation improves the efficacy of human mesenchymal stem cells after traumatic brain injury in rats

Traumatic brain injury is a leading cause of death and disability around the world. So far, drugs are not available to repair brain damage. Human mesenchymal stem cell (hMSC) transplantation therapy is a promising approach, although the inflammatory microenvironment of the injured brain affects the efficacy of transplanted hMSCs. We hypothesize that reducing the inflammation in the cerebral microenvironment by reducing pro-inflammatory chemokines prior to hMSC administration will improve the efficacy of hMSC therapy. In a rat model of lateral fluid percussion injury, combined pioglitazone (PG) and hMSC (combination) treatment showed less anxiety-like behavior and improved sensorimotor responses to a noxious cold stimulus. Significant reduction in brain lesion volume, neurodegeneration, microgliosis and astrogliosis were observed after combination treatment. TBI induced expression of inflammatory chemokine CCL20 and IL1-β were significantly decreased in the combination treatment group. Combination treatment significantly increased brain-derived neurotrophic factor (BDNF) level and subventricular zone (SVZ) neurogenesis. Taken together, reducing proinflammatory cytokine expression in the cerebral tissues after TBI by PG administration and prior to hMSC therapy improves the outcome of the therapy in which BDNF could have a role.

CCL20-CCR6 axis modulated traumatic brain injury-induced visual pathologies

BACKGROUND

Traumatic brain injury (TBI) is a major cause of death and disability in the USA and the world; it constitutes 30% of injury-related deaths (Taylor et al., MMWR Surveill Summ 66:1-16, 2017). Contact sports athletes often experience repetitive TBI (rTBI), which exerts a cumulative effect later in life. Visual impairment is a common after-effect of TBI. Previously, we have shown that C-C chemokine 20 (CCL20) plays a critical role in neurodegeneration and inflammation following TBI (Das et al., J Neuroinflammation 8:148, 2011). C-C chemokine receptor 6 (CCR6) is the only receptor that CCL20 interacts with. The objective of the present study was to investigate the role of CCL20-CCR6 axis in mediating rTBI-induced visual dysfunction (TVD).

METHODS

Wild type (WT) or CCR6 knock out (CCR6-/-) mice were subjected to closed head rTBI. Pioglitazone (PG) is a peroxisome proliferator-activated receptor γ (PPARγ) agonist which downregulates CCL20 production. Subsets of WT mice were treated with PG following final rTBI. A subset of mice was also treated with anti-CCL20 antibody to neutralize the CCL20 produced after rTBI. Histopathological assessments were performed to show cerebral pathologies, retinal pathologies, and inflammatory changes induced by rTBI.

RESULTS

rTBI induced cerebral neurodegeneration, retinal degeneration, microgliosis, astrogliosis, and CCL20 expression. CCR6-/- mice showed reduced retinal degeneration, microgliosis, and inflammation. Treatment with CCL20 neutralization antibody or PG showed reduced CCL20 expression along with reduced retinal degeneration and inflammation. rTBI-induced GFAP-positive glial activation in the optic nerve was not affected by knocking out CCR6.

CONCLUSION

The present data indicate that rTBI-induced retinal pathology is mediated at least in part by CCL20 in a CCR6-dependent manner.

Sitagliptin protects diabetic rats with acute myocardial infarction through induction of angiogenesis: role of IGF-1 and VEGF

Angiogenesis is regulated in a tissue-specific manner in all patients, especially those with diabetes. In this study, we describe a novel molecular pathway of angiogenesis regulation in diabetic rats with myocardial infarction (MI) and examine the cardioprotective effects of different doses of sitagliptin. Male rats were divided into 5 groups: normal vehicle group, diabetic group, diabetic + MI, diabetic + MI + 5 mg/kg sitagliptin, and diabetic + MI + 10 mg/kg sitagliptin. Isoproterenol in diabetic rats resulted in significant (p < 0.05) disturbance to the electrocardiogram, cardiac histopathological manifestations, and an increase in inflammatory markers compared with the vehicle and diabetic groups. Treatment with sitagliptin improved the electrocardiogram and histopathological sections, upregulated vascular endothelial growth factor (VEGF) and transmembrane phosphoglycoprotein protein (CD34) in cardiac tissues, and increased serum insulin-like growth factor 1 (IGF-1) and decreased cardiac tissue homogenate for interleukin 6 (IL-6) and cyclooxygenase 2 (COX-2). A relationship was found between serum IGF-1 and cardiac VEGF and CD34 accompanied by an improvement in cardiac function of diabetic rats with MI. Therefore, the observed effects of sitagliptin occurred at least partly through an improvement in angiogenesis and the mitigation of inflammation. Consequently, these data suggest that sitagliptin may contribute, in a dose-dependent manner, to protection against acute MI in diabetic individuals.

Inhibitory effect of valproate sodium on pain behavior in diabetic mice involves suppression of spinal histone deacetylase 1 and inflammatory mediators

Anti-epileptic medications are included in the international guidelines for managing neuropathic pain. Valproate sodium (VPS) was recently described as "the forgotten analgesic" and has been reported to relief pain in various models of neuropathic pain. Some studies reported anti-inflammatory and histone deacetylase 1 (HDA1) inhibitory properties for sodium valproate. The aim of the current study was to investigate the modulatory effect of VPS on pain behavior and inflammatory reactions in alloxan-induced diabetic neuropathy focusing on HDA1 inhibition and glia reactivity. 28 Male Swiss albino mice were allocated into four groups, (1) vehicle group, (2) alloxan-diabetic group, (3 & 4) alloxan+VPS (25 or 50 mg/kg) groups. VPS was given daily for 5 weeks by oral gavage. Pain behavior demonstrated increased allodynia (von-Frey filaments) and hyperalgesia (hot-plate test) in alloxan-diabetic mice that was reduced significantly by at least one of VPS doses. Sciatic nerves in diabetic mice showed increased histopathology score, increased silver staining for the nerves-indicating myelopathy- and a decrease in immunostaining for nerve growth factor. Spinal cord of diabetic mice showed greater histopathologic score, increased CD11b and glia fibrillary acidic protein (GFAP) immunostaining than vehicle treated mice. Molecular investigations highlighted greater content of spinal histone deacetylases, tumor necrosis factor-α (TNF-α) and interlukin-1β (IL1β) that were favorably modified by VPS. Overall, the current data confirmed that the pain killing and anti-inflammatory activity of VPS is at least partly mediated through inhibition of spinal HDA1 and glia reactivity. These findings support the view of inviting antiepileptics for treating neuropathies.

Fisetin attenuates isoproterenol-induced cardiac ischemic injury in vivo by suppressing RAGE/NF-κB mediated oxidative stress, apoptosis and inflammation

BACKGROUND

The therapeutic options for the reducing the damage caused by myocardial ischemia are limited and not devoid of adverse effects. The role of the flavanoid, fisetin, predominantly found in strawberry and apple, is yet to be explored in the heart.

STUDY DESIGN

Male Wistar rats (n = 48) were administered fisetin (10, 20 & 40 mg/kg/day, orally) or vehicle for 28 days while ISO, 85 mg/kg, subcutaneously, was also administered at 24 h interval on the 27th and 28th day. On the 29th day, rats were anaesthetized and right carotid artery was cannulated to record hemodynamic parameters. Subsequently, blood sample was collected and heart was removed to evaluate various parameters.

RESULTS

Fisetin at doses of 10 and 20 mg/kg reversed ISO induced detrimental alterations in blood pressure and left ventricular pressures and reduced the myocardial injury markers CK-MB and LDH in the serum. These findings were supported by amelioration of ISO induced histological and ultrastructural damage by fisetin. The disequilibrium in the levels of pro and anti oxidants in the myocardial tissue caused by ISO was also normalized Furthermore, apoptosis was evident from enhanced DNA fragmentation and raised pro-apoptotic proteins (bax, caspase-3, cytochrome-c) as well as suppressed anti-apoptotic protein (Bcl-2) in case of ISO treatment which again was reversed by fisetin. A molecular mechanism for this protection was elucidated as downregulation of RAGE and NF-κB However fisetin at 40 mg/kg revealed a deteriorating effect which was similar to ISO group of rats.

CONCLUSION

Hence, through our study, the role of fisetin in cardioprotection has been uncovered via a molecular pathway.

Nicotinamide Improves Functional Recovery via Regulation of the RAGE/JNK/NF-κB Signaling Pathway after Brain Injury

Brain injuries are a serious global health issue and are the leading cause of neurodegeneration. To date, there is no proper cure and treatment for brain-injury-induced neuropathological conditions because of a lack of sufficient knowledge and the failure to develop a drug due to the multi-pathological conditions in the brain. Herein, we explored the neurotherapeutic effects of Nicotinamide (NAM), against brain injury-induced neurodegeneration and behavioral problems. Treating injured mouse brains with NAM, for 7 days, significantly ameliorated several pathological events. Interestingly, NAM treatment significantly inhibited the injury-induced activation of receptor for advanced glycation end-products (RAGE), c-Jun N-terminal kinases (JNK), and neuroinflammatory mediators, such as NF-κB, TNF-α, IL-1β, and NOS2 in the brain, and it also regulated the levels of apoptotic markers, including Bax, caspase-3, and Bcl-2. Furthermore, treatment using NAM in TBI mice, significantly reversed synaptic protein loss and improved memory impairments and behavioral outcomes. Our findings suggested that NAM treatment reduced injury-induced secondary neurodegenerative pathology by modulating RAGE/JNK/NF-κB signaling in mice. Therefore, we recommend that NAM would be a safe and efficient therapeutic agent against brain-injury-induced neurodegeneration.

Composition of Ophiopogon Polysaccharide, Notoginseng Total Saponins and Rhizoma Coptidis Alkaloids Inhibits the Myocardial Apoptosis on Diabetic Atherosclerosis Rabbit

OBJECTIVE

To investigate the effects of Composition of Ophiopogon polysaccharide, Notoginseng total saponins and Rhizoma Coptidis alkaloids (CONR) on myocardial apoptosis of diabetic atherosclerosis (DA) rabbits METHODS: Sixty male New Zealand white rabbits were randomly divided into 6 groups [control group, model group, CONR high-dose group (450 mg/kg), CONR medium-dose group (150 mg/kg), CONR low-dose group (50 mg/kg), and simvastatin group] by using a completely random method, 10 in each group. DA model was established by intravenously injected alloxan combined with high-fat diet and abdominal aortic balloon injury. After mediation for 10 weeks, fasting blood glucose (FBG), glycosylated hemoglobin (GHB), glycosylated serum protein (GSP), fructoseamine (FRA), aldose reductase (AR), advanced glycation end products (AGEs) in serum were measured by enzyme linked immunosorbent assay (ELISA) method; the expression of receptor of AGEs (RAGE) in myocardial tissue were observed by immunohistochemical method; and p-Jun N-terminal kinase (p-JNK), caspase-3, B-cell lymphoma-2 (bcl-2) protein expression in myocardial tissue were measured by Western blotting. The myocardial apoptosis was detected by TdT-mediated dUTPnick-end labeling (TUNEL) method, and apoptosis index (AI) was calculated.

RESULTS

Compared with the control group, serum FBG, GHB, GSP, FRA, AR, AGEs and the expression of myocardium RAGE, p-JNK, caspase-3 proteins, as well as apoptosis index (AI) were significantly increased and bcl-2 protein was significantly decreased in the model group (P<0.01). Compared with the model group, the levels of serum FBG, GHB, GSP, FRA and AR showed a significant decline in CONR high- and medium-dose groups (P<0.01). FBG and GHB showed a significant decline in CONR low-dose group (P<0.01). Compared with the model group, the expression of serum AGEs and myocardium RAGE, p-JNK and caspase-3 protein as well as AI were significantly decreased and bcl-2 protein was significantly up-regulated in all treatment groups (P<0.01); high-dose CONR had the most significant effect on abovementioned indices compared with other treatment groups (P<0.01). Middle-dose CONR had better effect on serum AGEs compared with the low-dose group (P<0.01); middle-dose CONR and simvastatin groups had better effect on the expression of caspase-3, bcl-2 protein, myocardium apoptosis compared with the CONR low-dose group (P<0.01).

CONCLUSION

CONR may effectively inhibit myocardial apoptosis on DA rabbits by intervening AGEs-RAGE and JNK, caspase-3, and bcl-2 protein expressions.

Effect of pioglitazone on cardiometabolic profiles and safety in patients with type 2 diabetes undergoing percutaneous coronary artery intervention: a prospective, multicenter, randomized trial

Pioglitazone has superior antiatherosclerotic effects compared with other classes of antidiabetic agents, and there is substantial evidence that pioglitazone improves cardiovascular (CV) outcomes. However, there is also a potential risk of worsening heart failure (HF). Therefore, it is clinically important to determine whether pioglitazone is safe in patients with type 2 diabetes mellitus (T2DM) who require treatment for secondary prevention of CV disease, since they have an intrinsically higher risk of HF. This prospective, multicenter, open-label, randomized study investigated the effects of pioglitazone on cardiometabolic profiles and CV safety in T2DM patients undergoing elective percutaneous coronary intervention (PCI) using bare-metal stents or first-generation drug-eluting stents. A total of 94 eligible patients were randomly assigned to either a pioglitazone or conventional (control) group, and pioglitazone was started the day before PCI. Cardiometabolic profiles were evaluated before PCI and at primary follow-up coronary angiography (5-8 months). Pioglitazone treatment reduced HbA1c levels to a similar degree as conventional treatment (pioglitazone group 6.5 to 6.0%, P < 0.01; control group 6.5 to 5.9%, P < 0.001), without body weight gain. Levels of high-molecular weight adiponectin increased more in the pioglitazone group than the control group (P < 0.001), and the changes were irrespective of baseline glycemic control. Furthermore, pioglitazone significantly reduced plasma levels of natriuretic peptides and preserved cardiac systolic and diastolic function (assessed by echocardiography) without incident hospitalization for worsening HF. The incidence of clinical adverse events was also comparable between the groups. These results indicate that pioglitazone treatment before and after elective PCI may be tolerable and clinically safe and may improve cardiometabolic profiles in T2DM patients.

Obesity in pregnancy as a model to identify women at risk for later metabolic syndrome

The aim of our study is to identify - in a cohort of obese women - cardiovascular and clinical risk factors in women with previous complicated pregnancies and protective factors in women with previous physiological pregnancies. A total of 135 nonpregnant obese women referring to Policlinico Gemelli in Rome were prospectively collected in 2009-2010. Thirty-two women matched inclusion criteria: 16 reported a previous physiological pregnancy and 16 reported previous obstetric complications. A clinical, instrumental and laboratory evaluation has been performed for each patient. Statistical analysis was performed using StatView Software. Values are expressed as mean ± standard error (SEM). All tests were two-tailed with a confidence level of 95% (p < .05). Statistically significant reduced flow-mediated dilatation (p = .0338), increased serum values of vascular cell adhesion molecule (p = .0154) and higher systolic blood pressure values (p = .0427) have been detected in obese women with previous complicated pregnancies due to gestational diabetes and/or hypertension. In conclusion, obese patients with previous complicated pregnancies develop signs of endothelial dysfunction in the postpartum period. Future research should focus on the early identification of possible molecular mechanisms implicated in the development of glyco-metabolic and cardiovascular diseases in obese patients, since they are at higher risk of metabolic syndrome.

Myocyte membrane and microdomain modifications in diabetes: determinants of ischemic tolerance and cardioprotection

Cardiovascular disease, predominantly ischemic heart disease (IHD), is the leading cause of death in diabetes mellitus (DM). In addition to eliciting cardiomyopathy, DM induces a ‘wicked triumvirate’: (i) increasing the risk and incidence of IHD and myocardial ischemia; (ii) decreasing myocardial tolerance to ischemia–reperfusion (I–R) injury; and (iii) inhibiting or eliminating responses to cardioprotective stimuli. Changes in ischemic tolerance and cardioprotective signaling may contribute to substantially higher mortality and morbidity following ischemic insult in DM patients. Among the diverse mechanisms implicated in diabetic impairment of ischemic tolerance and cardioprotection, changes in sarcolemmal makeup may play an overarching role and are considered in detail in the current review. Observations predominantly in animal models reveal DM-dependent changes in membrane lipid composition (cholesterol and triglyceride accumulation, fatty acid saturation vs. reduced desaturation, phospholipid remodeling) that contribute to modulation of caveolar domains, gap junctions and T-tubules. These modifications influence sarcolemmal biophysical properties, receptor and phospholipid signaling, ion channel and transporter functions, contributing to contractile and electrophysiological dysfunction, cardiomyopathy, ischemic intolerance and suppression of protective signaling. A better understanding of these sarcolemmal abnormalities in types I and II DM (T1DM, T2DM) can inform approaches to limiting cardiomyopathy, associated IHD and their consequences. Key knowledge gaps include details of sarcolemmal changes in models of T2DM, temporal patterns of lipid, microdomain and T-tubule changes during disease development, and the precise impacts of these diverse sarcolemmal modifications. Importantly, exercise, dietary, pharmacological and gene approaches have potential for improving sarcolemmal makeup, and thus myocyte function and stress-resistance in this ubiquitous metabolic disorder.

Cardiotoxic effect of levofloxacin and ciprofloxacin in rats with/without acute myocardial infarction: Impact on cardiac rhythm and cardiac expression of Kv4.3, Kv1.2 and Nav1.5 channels

Prolongation of QT interval is possible with fluoroquinolones, yet the underlying contributing factors have not been elucidated. Two widely used fluoroquinolone drugs were at the focus of this study in rats with/without acute myocardial dysfunction (AMI) induced by isoproterenol. The effects of levofloxacin and ciprofloxacin on the cardiac mRNA expression of rat Kv4.3, Kv1.2 and Nav1.5 mRNAs were determined. Administration of the two antibiotics produced dose-dependent changes in ECG parameters that were more prominent in rats with AMI than healthy rats; this was accompanied by elevations in serum lactate dehydrogenase and creatine kinase-MB. Histopathological examination indicated some loss of striations, edema and fibrotic changes in rats with AMI; however the two antibiotics did not further exacerbate the cardiac histopathology. mRNA expression of the ion channels was altered in rats with AMI and healthy rats. In conclusion, long-term administration of levofloxacin and ciprofloxacin produced deleterious effects on the ECG pattern of rats with/without AMI. The effect was generally baseline-dependent and therefore, rats with AMI showed greater ECG disturbances and increases in cardiac enzymes. Taken together, these data make it advisable to monitor patients with a history of acute AMI requiring treatment with these antibiotics until data from human studies are available.

Plausible Roles for RAGE in Conditions Exacerbated by Direct and Indirect (Secondhand) Smoke Exposure

Approximately 1 billion people smoke worldwide, and the burden placed on society by primary and secondhand smokers is expected to increase. Smoking is the leading risk factor for myriad health complications stemming from diverse pathogenic programs. First- and second-hand cigarette smoke contains thousands of constituents, including several carcinogens and cytotoxic chemicals that orchestrate chronic inflammatory responses and destructive remodeling events. In the current review, we outline details related to compromised pulmonary and systemic conditions related to smoke exposure. Specifically, data are discussed relative to impaired lung physiology, cancer mechanisms, maternal-fetal complications, cardiometabolic, and joint disorders in the context of smoke exposure exacerbations. As a general unifying mechanism, the receptor for advanced glycation end-products (RAGE) and its signaling axis is increasingly considered central to smoke-related pathogenesis. RAGE is a multi-ligand cell surface receptor whose expression increases following cigarette smoke exposure. RAGE signaling participates in the underpinning of inflammatory mechanisms mediated by requisite cytokines, chemokines, and remodeling enzymes. Understanding the biological contributions of RAGE during cigarette smoke-induced inflammation may provide critically important insight into the pathology of lung disease and systemic complications that combine during the demise of those exposed.

Predictive Nomogram of RAGE Genetic Polymorphisms and Metabolic Risk Factors for Myocardial Infarction Risk in a Han Chinese Population

We investigated the association of 4 well-characterized polymorphisms in receptor for the advanced glycation end-product ( RAGE) gene with myocardial infarction (MI) risk and the changes in metabolic risk factors among 717/612 patients/controls, with the aim of constructing a predictive nomogram. The genotype/allele distributions differed significantly between the 2 groups for T-429C ( Pgenotype/allele = .004/.001) and G1704T ( P < .001/.001). T-429C was significantly associated with MI risk, especially under a recessive model (adjusted odds ratio: 2.24, 95% confidence interval: 1.33-3.79, P = .003). For G1704T, significance was detected under additive (1.37; 1.12-1.67; P = .002) and recessive (3.86; 2.27-6.57; P < .001) models. There were significant differences in blood pressure and low-density lipoprotein cholesterol (LDL-C) across T-429C genotypes and in total cholesterol and LDL-C across G1704T genotypes. The overall best multifactor dimensionality reduction model included dyslipidemia, G1704T, and T-429C. Further predictive nomogram on 2 significant polymorphisms, blood pressure and lipids, showed a better predictive capability (concordance index = 0.716, P < .001). Altogether, we identified 2 polymorphisms of RAGE, T-429C and G1704T, which interacted with metabolic risk factors associated with the occurrence of MI. We also constructed a genetic–metabolic nomogram that can better predict MI risk.